Hamas says the head of its military wing, Ahmed Said Khalil al-Jabari, has been killed in an Israeli air strike,according to BBC.
Witnesses said he was travelling in a car in Gaza City when it exploded.
“Israel’s Shin Bet” said Jabari was responsible for “all activities against “Israel” from Gaza” in the last decade.
Jabari is the most senior Hamas official to be killed in Gaza since an “Israeli” offensive four years ago.
Since Saturday, four Palestinian civilians and three militants, including Jabari, have been killed in Gaza, and dozens injured.
The BBC’s Jon Donnison in Gaza City says the sound of gunfire echoed through the streets after Wednesday’s air strike, which killed Jabari.
There are fears the attack could lead to another war, he adds.
Jabari’s bodyguard, who was in the car with the commander of the Izz al-Din al-Qassam Brigades, is also believed to have died. Earlier reports said it was his deputy.
Jabari, 46, was one of Hamas’s most senior figures.