Hamas has said one of its top officials, Saleh al Arouri, has been killed in an explosion in Beirut - blaming the "cowardly assassination" on Israel.
Al Arouri was one of the founders of Hamas's military wing and the deputy leader of the group's political bureau. He also headed Hamas's presence in the West Bank.
Lebanon's state-run National News Agency said the blast killed four people and was carried out by an Israeli drone. Three security sources told Reuters the strike hit Beirut's southern suburbs of Dahiyeh.
Izzat Al-Rishq, a member of the political bureau of Hamas, has said al Arouri was killed in a "cowardly assassination" by Israel, adding such attacks "will not succeed in breaking the will and steadfastness of our people, or undermining the continuation of their valiant resistance".
He added: "It proves once again the abject failure of this enemy to achieve any of its aggressive goals in the Gaza Strip."
Sayyed Hassan Nasrallah, leader of the Iranian-backed Hezbollah group in Lebanon, earlier vowed to retaliate against any Israeli targeting of Palestinian officials in the country.
Israel's Prime Minister Benjamin Netanyahu had threatened to kill al Arouri even before the Hamas-Israel war began on 7 October 2023.
Hamas official Bassem Naim has confirmed al Arouri was killed in the blast. A Hezbollah official speaking on condition of anonymity in line with regulations also said al Arouri was killed.
Israeli officials declined to comment.
An explosion shook the Lebanese capital's southern suburbs on Tuesday evening causing chaos in Hezbollah's stronghold, but the nature of the blast was not immediately known.
