Watch live: Israel marks 1 year since Oct. 7 Hamas attack

It’s been one year since Hamas launched a surprise attack into Israel, killing more than 1,000 Israelis and sparking a year-long war that has killed nearly 42,000 Palestinians and widened conflicts in the Middle East. 

The FBI has warned of potential violence on the grim anniversary of the attacks, citing "further significant escalations" that could fuel violent extremists. 

Security forces in several countries warned of heightened levels of alert in major cities on Monday, amid concerns that the escalating conflict in the Middle East could inspire new terror attacks in Europe or that some of the protests could turn violent.

A man walks past shelter tents erected near collapsed buildings in the Bureij camp for Palestinian refugees in the central Gaza Strip on October 1, 2024 amid the ongoing war in the Palestinian territory between Israel and Hamas. (Photo by EYAD BABA/A

Massive rallies and protests were held around the world over the weekend, with thousands participating in both pro-Palestinian and pro-Israel demonstrations. Other events calling for an immediate ceasefire are expected Monday. 

Pope Francis on Sunday repeated his plea for "an immediate ceasefire on every front," including Lebanon. French President Emmanuel Macron has also called for an immediate cease-fire in both Gaza and Lebanon. 

"The priority is … that we stop delivering weapons to fight in Gaza," Macron said, drawing criticism from Israel’s Prime Minister Benjamin Netanyahu. 

Meanwhile, in the U.S., President Biden, Vice President Harris and former President Donald Trump are marking the anniversary. 

Trump will visit the New York City gravesite of Rabbi Menachem Mendel Schneerson, who led the Chabad-Lubavitch movement of Orthodox Judaism from 1951 until his death in 1994. Schneerson was the movement’s seventh leader, known as Lubavitcher Rebbe. Trump then will speak before Jewish community leaders at one of his Florida resorts in the Miami suburb of Doral.

Harris will briefly speak to journalists and, with her husband, plant a pomegranate tree on the grounds of the Vice President’s Residence in honor of the those killed a year ago.

Earlier Monday, Harris’ husband Doug Emhoff, who is Jewish, recited a prayer for peace at an event to commemorate the anniversary hosted by the American Jewish Committee in Washington.

President Joe Biden marked the occasion in a somber event in the White House Blue Room, lighting a memorial candle to mark the anniversary.

What’s the latest in the Israel-Hamas war? 

Israel has escalated its strikes in Gaza and launched its ground incursion into Lebanon last week, where they have clashed along the border with militants from the powerful Hezbollah group. 

RELATED: Palestinian "tent life" TikTok star Medo Halimy dies in Israeli air strike

In a surprise move in mid-September, Israel was able to detonate the pagers used by Hezbollah officials to communicate, killing several people and wounding thousands more. A day later, walkie-talkies and solar equipment exploded in Beirut, killing at least 20 people. 

On Sept. 28, Hezbollah leader Hassan Nasrallah was killed in an Israeli airstrike in Beirut. A few days later, Iran launched missiles at Israel

Israel and the United States have warned there would be severe consequences if Iran attacks, though so far there has only been discussion of what the U.S. and Israel may do in response, including strikes on Iran's oil facilities. 

What happened on Oct. 7, 2023?

On Oct. 7 last year, Hamas launched a surprise attack into Israel, killing 1,200 Israelis, taking 250 people hostage and setting off a war with Israel that has shattered much of the Hamas-controlled Gaza Strip.

More than 41,000 Palestinians have been killed since then in Gaza, according to the Gaza Health Ministry, which does not differentiate between fighters and civilians. It says more than half were women and children.

In late September, Israel shifted some of its focus to Hezbollah, which holds much of the power in parts of southern Lebanon and some other areas of the country, attacking the militants with exploding pagers, airstrikes and, eventually, incursions into Lebanon.

How many hostages remain in Gaza? 

Of the 250 hostages taken on Oct. 7, nearly 100 Israeli hostages remain in Gaza, with fewer than 70 believed to be alive. 

Hersh Goldberg-Polin, a 23-year-old Israeli-American and one of the most recognizable faces of the devastating hostage crisis, was found dead with five other hostages on Aug. 31. 

RELATED: Hersh Goldberg-Polin's parents deliver heartbreaking eulogy after son slain by Hamas

"Amidst the inexplicable agony, terror, anguish, desperation and fear, we became absolutely certain that you were coming home to us alive. But it was not to be," Rachel Goldberg-Polin said in her eulogy. "If there was something we could’ve done to save you and we didn’t think of it, I beg your forgiveness. We tried so very hard, deeply and desperately, I’m sorry."

His parents have said they hope Goldber-Polin’s death can be a global symbol for peace. 

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