Yahya Sinwar (C), Hamas' leader in the Gaza Strip, waves to supporters at a rally marking the 35th anniversary of the establishment of the movement in Gaza City, on Dec. 14, 2022. (Photo by Rizek Abdeljawad/Xinhua)

GAZA, Aug. 6 (Xinhua) -- Hamas announced on Tuesday the selection of Yahya Sinwar as its political bureau chief, replacing late chief Ismail Haniyeh, who was assassinated in Tehran last week.

"We announce the selection of leader Yahya Sinwar as head of the movement's political bureau, succeeding leader Ismail Haniyeh," Hamas said in a statement.

Hamas' leader Yahya Sinwar Home (2R) is seen during a rally by Ezz al-Din al-Qassam brigades (the military wing of Hamas) rally to commemorate the militants who were killed in Israeli bombardment of a tunnel in Gaza City, on May 24, 2021. (Photo by Rizek AbdeljawadXinhua)

Sinwar, 61, has been the Hamas leader in the Gaza Strip since 2017. He spent more than 20 years in Israeli prisons and was released under a prisoner exchange deal with Israel in 2011. He is considered by Israel as one of the main planners of the Oct. 7, 2023 attack on Israel.

Haniyeh was killed in Tehran on July 31, which Hamas attributed to a "treacherous" Israeli raid on his residence.