Israel-Hamas conflict: Timeline and key developments

More than a week after Hamas terrorists rained thousands of rockets down on Israel and infiltrated the country by air, sea and land in an unprecedented surprise attack, the region stands on the brink of war — with fears of a wider conflict and thousands dead on both sides of the Israel-Gaza border.

The conflict was touched off by the Oct. 7 sneak attack, which included thousands of armed Hamas fighters breaching a border security fence and indiscriminately gunning down Israeli civilians and soldiers taken off guard. Other militants stormed beaches in Israel in motorboats and some brought death from the sky, swooping in on paragliders.

More than 1,400 people have been killed in Israel, including children, and another 3,400 people have been injured, Israeli officials said. Roughly 200 to 250 hostages were taken by Hamas and it is believed they are being held in Gaza. At least 3,000 people have been killed in Gaza and about 12,500 have been injured, according to the Palestinian Health Authority.

Israeli soldiers remove the body of a compatriot, killed during an attack by the Palestinian militants, in Kfar Aza, south of Israel bordering Gaza Strip, on Oct.10, 2023. Israel pounded Hamas targets in Gaza and said the bodies of 1,500 Islamist militants were found in southern towns recaptured by the army in grueling battles near the Palestinian enclave.

Jack Guez/AFP via Getty Images

Israel has responded with a barrage of airstrikes that have decimated the Gaza Strip, leaving more than 300,000 residents displaced. Israel has warned more than 1 million Palestinians to move to a safer part of the territory in southern Gaza or potentially face the wrath of 400,000 Israeli soldiers prepped to annihilate Hamas militant units, many believed to be hiding in a miles-long network of tunnels under residential neighborhoods.

And many fear those trapped in Gaza, including an estimated 400 Americans, are on the cusp of a humanitarian disaster with no electricity or running water, and a food supply that is dwindling by the hour.

Here are the key developments that have happened so far in the war:

Israeli soldiers remove the body of a compatriot, killed during an attack by the Palestinian militants, in Kfar Aza, south of Israel bordering Gaza Strip, on Oct.10, 2023. Israel pounded Hamas targets in Gaza and said the bodies of 1,500 Islamist militants were found in southern towns recaptured by the army in grueling battles near the Palestinian enclave.

Jack Guez/AFP via Getty Images

A barrage of rocketsOct. 7, 6:30 a.m. in Israel

Air raid sirens begin sounding in Jerusalem around 6:30 a.m. local time, warning citizens of the attack in progress and to immediately take cover. An estimated 2,200 rockets were fired toward southern and central Israel, including Tel Aviv and Jerusalem, by the Hamas militants, according to the Israel Defense Forces. Meanwhile, Hamas claims at least 5,000 rockets were fired, all landing in southern and central Israel.

Israeli troops inspect a damaged house in the southern Israeli city of Ashkelon after a rocket attack from Gaza on Oct. 9, 2023.

Menahem Kahana/AFP via Getty Images

Armed Hamas militants, many on motorcycles, storm blockaded areas of the Gaza Strip, shooting at Jewish settlers and slaughtering people at kibbutzim and small towns. Video footage surfaces of Hamas militants taking Israeli citizens — including mothers, children and the elderly — hostage and carrying them across the Gaza border.

Oct. 7, shortly after the attack begins

Mohammed Deif, commander in chief of Hamas’ military arm, Al Qassam Brigades, releases a video statement claiming responsibility for the attack.

‘Israel is at war’

Israeli jet fighters launch retaliatory strikes in Gaza. Video surfaces of a high-rise residential building and the Al-Sousi Mosque in Gaza City being bombed and flattened.

Israeli Prime Minister Benjamin Netanyahu tells his country, “Israel is at war.”

President Joe Biden tells Netanyahu in a phone call that the United States “condemns” Hamas’ assault and has Isreal’s back. In a televised address from the White House, Biden says, “Israel has a right to defend itself and its people.”

30 Israeli police killed in fightingOct. 8

At least 30 Israeli police officers are killed in the fighting, mainly in Sderot, Israel, where Hamas gunmen took control of the police station.

Israeli officials announce that fighting is ongoing in six places, including Sderot — which sits just 2 miles from the border with Gaza — and that a rocket injured four people.

Palestinians inspect the rubble of a building after it was struck by an Israeli airstrike, in Gaza City, Oct. 8, 2023.

Fatima Shbair/AP

Videos posted online show a packed all-night music festival in a desert in southern Israel near the Gaza border being attacked by rockets and armed Hamas fighters on the ground. The footage shows women and children being dragged away in vehicles and driven back into Gaza. Israeli rescue service Zaka says at least 260 bodies were removed from the venue following the attack.

Secretary of State Antony Blinken tells ABC’s “This Week” anchor George Stephanopoulos that the U.S. has pledged its full support to Israel and says, “The world should be revolted at what it’s seen.”

Oct. 9, morning

Air sirens sound in northern Israel, prompting residents to rush to safe rooms. The Israel Defense Forces claimed at least two rockets were fired toward northern Israel from Lebanon. One of the rockets, according to the IDF, landed in Lebanese territory.

“The IDF neutralized a number of terrorist infiltrators who crossed from Lebanon into Israel. We are defending our country and stand ready on all borders,” the IDF says in a statement.

An official with the U.S. National Security Council confirms there were nine Americans killed in Israel. The death toll would continue to climb.

An Israeli sodleir prays standing in front of a Merkava tank on the outskirts of the northern town of Kiryat Shmona near the border with Lebanon on Oct. 8, 2023.

Jalaa Marey/AFP via Getty Images

The IDF announces its jet fighters struck 130 targets in the Gaza Strip, and Israeli Defense Minister Yoav Gallant orders a “complete siege” of Gaza, cutting electricity to the region and blocking fuel and food from entering the territory from Israel.

The IDF announces it has mobilized 300,000 reserves — the largest and quickest call-up in Israel’s history.

Hamas says the group will start killing Israeli hostages one by one and film the executions unless Israel immediately stops shelling homes in Gaza without warning.

‘Pure, unadulterated evil’Oct. 10

The U.S. confirms that an undetermined number of Americans had been taken hostage by Hamas.

“I’ve directed my team to share intelligence and deploy additional experts from across the United States government to consult with and advise Israeli counterparts on hostage recovery efforts. Because as president, I have no higher priority than the safety of Americans being held hostage around the world,” Biden says.

Israeli forces cross a main road in their armoured personnel carrier (APC) as additional troops are deployed near the southern city of Sderot on Oct. 8, 2023.

Menahem Kahana/AFP via Getty Images

Biden says the atrocities committed by Hamas fighters included the “slaughter” of men, women and entire families, as well as “stomach-churning reports of babies being killed.”

Gallant tours southern Israel along the Gaza border, telling soldiers they are moving to “a full-scale response” to the Hamas surprise attack and that he has “removed every restriction.”

“Hamas wanted to see a change in Gaza — the reality is Gaza will make a 180. They will regret [their actions],” Gallant said.

Israeli forces cross a main road in their armoured personnel carrier (APC) as additional troops are deployed near the southern city of Sderot on Oct. 8, 2023.

Menahem Kahana/AFP via Getty Images

Oct. 13

The IDF calls for “all residents of Gaza City to evacuate their homes” and “move south for their protection.”

Palestinians with their belongings flee northern Gaza City following the Israeli army’s warning to leave their homes before an expected ground offensive, in Gaza City on Oct. 13, 2023.

Mahmud Hams/AFP via Getty Images

Blinken meets with Palestinian Authority President Mahmoud Abbas in Jordan and conveys the need to cool tensions across the West Bank and prevent the conflict from broadening. Blinken also expresses condolences to the families of those killed in Gaza

Biden speaks with family members of Americans who remain unaccounted for after the attack in Israel.

The first chartered flight to evacuate Americans from Israel departs for Europe.

Hundreds of Palestinian families with their belongings flee following the Israeli army’s warning to leave their homes and move south before an expected ground offensive, in Gaza City on Oct. 13, 2023.

Mahmud Hams/AFP via Getty Images

Attempted mass exodus from Gaza delayed at Egypt borderOct. 14

Egypt, Israel and the United States agree to allow foreigners in Gaza to pass through the Rafah border crossing into Egypt, causing a chaotic rush to the southern border by Palestinians and foreigners hoping to escape. But no firm timeline is set on when the border will open.

The IDF announces it is preparing to implement an “integrated and coordinated attack from the air, sea and land” with an emphasis on a “significant ground operation.”

Oct. 15

Sari Bashi, program director for Human Rights Watch, tells ABC News Live that the situation in Gaza is “about as bad as it can get.”

“People are being forced to drink brackish, untreated water because the price of bottled water has gone up beyond what most people can afford,” Bashi says. “Food is short, there is no electricity. Even emergency generators that hospitals have are running low on fuel, and supplies are dwindling.”

The number of U.S. citizens killed in the Hamas attack on Israel rises to 30. At least 13 American nationals are still missing, a State Department spokesperson says.

Biden to go to the Middle EastOct. 16

The Israel Defense Forces say the number of hostages taken by Hamas has climbed to 199.

Hamas says it is holding between 200 and 250 hostages and releases video of one of them, 21-year-old Mia Shem, who was abducted at the Supernova music festival attacked by the terrorist group.

Ronen Bar, director of Israel’s Shin Bet security service, says in a letter that he takes responsibility for the Israeli intelligence failure that aided the Hamas attack, saying, “We were unable to generate a sufficient warning for [the] Hamas’ attack.”

The White House announces Biden will visit Israel.

Oct. 17

The Pentagon confirms that 2,000 U.S. troops have been put on a heightened state of readiness for possible deployment to the Middle East, a Pentagon official said Tuesday morning.

Overnight Israeli air raids killed at least 71 people and injured at least 50 others in Gaza, the Palestinian Health Ministry says.

At least 500 people are killed in an explosion at the Al Ahli Arab Hospital in the middle of Gaza City, which was being used to shelter thousands of displaced residents, the Gaza Health Ministry says.

The IDF denies responsibility for the blast, saying a failed rocket launch by the Palestinian Islamic Jihad caused it. Netanyahu says, “The barbaric terrorists in Gaza are the ones who attacked the hospital.” A senior U.S. official tells ABC News that U.S. officials at this point “just don’t know where the rocket came from.”

Biden arrives in IsraelOct. 18

Under the threat of rocket strikes and heightened security, President Biden arrives in Israel Wednesday morning and is greeted with an embrace by Prime Minister Netanyahu on the tarmac of Ben Gurion Airport near Tel Aviv.

During a joint appearance with Netanyahu, Biden says he is “proud to be here.”

“I want to say to the people of Israel, their courage, their commitment, their bravery is stunning, it’s really stunning,” Biden says, vowing to supply Israel with whatever it needs to defend itself.

In response, Netanyahu says, “Thank you, Mr. President. Thank you for standing with Israel today, tomorrow and always.”

At the Vatican in Rome, Pope Francis appeals for peace in the Middle East.

“Today our thoughts go to Israel and Palestine,” the pope says. “Casualties are rising and the situation in Gaza is desperate. Please do everything possible to avoid a humanitarian catastrophe.”