Ismail Haniyeh, who was killed in Tehran, according to Hamas and Iranian media, was a longtime political leader of the militant group.
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 United States soon after.
Over the years, he 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.
At the time, Haniyeh – who was based in Qatar – insisted their deaths would not affect ongoing ceasefire and hostage talks.