Ismail Haniyeh, the group’s former leader, was slain in Tehran last month in what Hamas described as a “treacherous Zionist raid on his residence”.
Israel hasn’t claimed credit for the incident.
Who is Hamas’ leader, Yahya Sinwar?
Sinwar, the mastermind of the raid that saw Hamas militants penetrate southern Israel, kill 1,200 people, and kidnap 250 more, has been picked to succeed Haniyeh.
In retaliation, Israel’s military onslaught has killed almost 40,000 Palestinians, according to Hamas’ health ministry, and destroyed the densely populated enclave.
The Islamic resistance movement Hamas announces the selection of Commander Yahya Sinwar as chairman of the political bureau.
The statement was welcomed with a barrage of rockets from Gaza by militants still battling in the confined enclave.
It comes as Israel continues to prepare for a reaction to the killing of Haniyeh.
“The appointment means that Israel needs to face Sinwar over a solution to the Gaza war,” said a regional official acquainted with the discussions facilitated by Egypt and Qatar, which aim to bring an end to the fighting in Gaza and return the 115 Israeli and international captives currently held in the territory.