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Hamas leader Ismail Haniyeh was assassinated in Tehran, Iran's paramilitary Revolutionary Guard said early on Wednesday, and Hamas blamed Israel for the attack.
Israel has vowed to kill Haniyeh and other leaders of Hamas over the group's October 7 attack on Israel that killed 1200 people and saw some 250 others taken hostage.
An Israeli military spokesman did not immediately respond to a request for comment. Israel often doesn't when it comes to assassinations carried out by their Mossad intelligence agency.
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Hamas said Haniyeh was killed "in a Zionist airstrike on his residence in Tehran after he participated in the inauguration of Iran's new president".
"Hamas declares to the great Palestinian people and the people of the Arab and Islamic nations and all the free people of the world, brother leader Ismail Ismail Haniyeh a martyr," the terse statement said.
Haniyeh left the Gaza Strip in 2019 and had lived in exile in Qatar.
The top Hamas leader in Gaza is Yehya Sinwar, who masterminded the October 7 attack.
Haniyeh was in Tehran to attend Iran's President Masoud Pezeshkian's swearing-in ceremony on Tuesday.
Iran gave no details on how Haniyeh was killed, and the Guard said the attack was under investigation.
Analysts on Iranian state television immediately began blaming Israel for the attack.
There was no immediate reaction from the White House.
The apparent assassination comes at a precarious time, as the Biden administration has tried to push Hamas and Israel to agree to at least a temporary cease-fire and hostage-release deal.
CIA Director Bill Burns was in Rome on Sunday to meet with senior Israel, Qatari and Egyptian officials in the latest round of talks. Separately, Brett McGurk, the White House Coordinator for the Middle East and North Africa, is in the region for talks with US partners.
Israel is suspected of running a years-long assassination campaign targeting Iranian nuclear scientists and others associated with its atomic program.
In 2020, a top Iranian military nuclear scientist, Mohsen Fakhrizadeh, was killed by a remote-controlled machine gun while traveling in a car outside Tehran.
In Israel's war against Hamas since the October attack, more than 39,360 Palestinians have been killed and more than 90,900 wounded, according to the Gaza Health Ministry, whose count does not differentiate between civilians and combatants.
Who is Ismail Haniyed?
Haniyeh was a longtime political leader of the militant group Hamas.
The 62-year-old was born in a refugee camp near Gaza City, and joined Hamas in the late 1980s during the First Intifada, or uprising.
As Hamas grew in power, Haniyeh rose through the ranks – being appointed part of a secret "collective leadership" in 2004, then being named the prime minister of the Palestinian Authority in 2006.
By 2017 he had become chief of the group – and was named a "specially designated global terrorist" by the US soon after.
Over the years, he has participated in peace talks with former US President Jimmy Carter, and met with other world leaders including the Emir of Qatar, Sheikh Hamad bin Khalifa al-Thani, and Chinese diplomat Wang Kejian earlier this year.
In April, Israeli airstrikes killed three of Haniyeh's sons and four of his grandchildren, according to Hamas.
– Reported with CNN, AP
