The Israeli military said the strike targeted a "military structure" and killed Muamen Ahmed, who it described as a military operative who had taken a direct part in combat against Israeli forces.
It gave no mention of a wife or children but said Ahmed had recently been "advancing terror attacks" against Israeli forces.
Health officials and relatives in the Gaza Strip confirmed that Ahmed had been killed in Beit Lahiya but made no comment on his alleged activities.
At al-Shifa Hospital, friends and relatives flocked to pay their respect as the white-shrouded bodies of the family members were laid on the ground before being taken to burials.
Zuhair al-Haisami, a neighbour of the victims, said an air strike had hit their home at 2am, while they were sleeping.
"There isn't any truce," he said.
"Not a single day passes without martyrs, or (people being) injured," he added.
An October 2025 US-backed ceasefire halted large-scale fighting but it has not ended Israeli strikes and there has been little progress on steps towards permanent peace.
Hamas accuses Israel of violating the ceasefire and undermining efforts to implement US President Donald Trump's broader plan to end the Gaza Strip conflict, which includes the Israeli withdrawal from the enclave and the disarmament of Hamas.
Israel says Hamas has been violating the deal.
More than 1300 Palestinians, mostly civilians, have been killed in the Gaza Strip since the ceasefire took effect, according to the territory's health officials, while the Israeli military says four Israeli soldiers have been killed.
Hamas does not usually disclose information about fatalities among its fighters.
The Israeli military struck at least six homes across the Gaza Strip in the past two days, causing damage to nearby houses and tent shelters and forcing many families to flee, residents and medics said.
Some owners of the houses, or their neighbours, got a call from the military ordering them to leave the area shortly before missiles struck the buildings, residents said.
The Israeli military did not comment directly on the strikes on houses but said on Wednesday it had hit three areas across the Gaza Strip and dismantled three Hamas weapons storage facilities.
On Tuesday, Israeli security forces said they had dismantled another three weapons depots belonging to Hamas and Islamic Jihad.
Ismail al-Thawabta, director of the Hamas-run Gazan government media office, denied Israeli allegations, saying that Israel's targets were "the civilians and their homes".
The 2023 Hamas-led attacks killed 1200 people in Israel while another 251 were taken hostage, according to Israeli tallies.
More than 73,000 Palestinians have been killed in Israel's military campaign, according to Gazan health authorities.
