Hamas says its deputy head Saleh al-Arouri has been killed in a blast in Beirut, reports BBC.
He is said to have been among four people killed in an explosion at Hamas`s office in Dahiyeh, one of the Lebanese capital`s southern suburbs.
Al-Arouri was the deputy head of Hamas`s political bureau and known to be deeply involved in its military affairs.
Elsewhere, the Palestinian Red Crescent says five people have been killed and three injured in Israeli bombing on its headquarters in Khan Younis, in south Gaza.
Intense fighting has continued in the territory, even as Israel announced plans to pull back some combat troops.
Meanwhile, the Israeli military says its troops have killed dozens of Palestinian fighters in Jabalia in the north, and targeted others in Gaza City and coastal areas.
At least 1,200 people were killed when Hamas militants attacked Israel on 7 October and about 240 others were taken hostage.
The Hamas-run health ministry in Gaza says more than 22,000 people have been killed in the territory since Israel started its retaliatory campaign.
