Israel has defended an airstrike on a van in Gaza that killed nine Palestinian civilians, two of them children. The vehicle was being used to transport rockets. The Israeli army said it targeted the van because it was carrying powerful weapons that could have been used against Israel.Witnesses said an aircraft fired two missiles. The first hit the vehicle, causing it to crash into the pavement. A second missile hit as a crowd gathered and rescuers arrived. Two Islamic Jihad militants were also killed and some 30 other people wounded. The incident seems certain to fuel a recent upsurge of violence. A senior member of the ruling Hamas militant group indicated it would retaliate. Mushir al-Masri described the deaths in Gaza as “war crimes”, adding that Israel was in, what he called, “open war” with “innocent Palestinian people.” Saeb Erekat of President Mahmoud Abbas’s ruling Fatah faction called for restraint. “We condemn, in the strongest possible terms, this Israeli military escalation. Nine Palestinians have been killed this morning and I’m afraid to say that violence will continue to breed more violence.” The airstrike follows on from the killings of seven Palestinian civilians on a beach on Gaza last Friday in a blast militants have blamed on Israel. Hamas ended its 16 month old ceasefire in response. An Israeli investigation said the explosion was caused by a land mine planted by militants.