Hamas' top political leader was killed Wednesday by a predawn airstrike in the Iranian capital, Iran and the militant group said, blaming Israel for a shock assassination that risked escalating into an all-out regional war.

An Israeli air strike has killed the son of Hamas' chief ‌negotiator in US-mediated talks over the Gaza Strip's future, as leaders of the militant group held talks in Cairo aimed at safeguarding their truce with Israel.