The Israeli military killed five Palestinians, including three children, when they fired a missile at a car in Gaza this afternoon.
The Israeli army confirmed the strike on a car carrying the two militants, which came on the eve of formal campaigning for Israel's elections at the end of the month and after interim Prime Minister Ehud Olmert said he would use what he called "an iron fist" against militants.
Palestinians react at the scene of today's killings
Two occupants of the car were killed when the Israeli missile struck their vehicle in northern Gaza this afternoon.
Eight-year-old boy, Raed al-Batsh, and 15-year-old Ahmed al-Sweissi, who were standing in Salaheddin Street at the time, were also killed in the massive explosion.
Another 15-year-old boy died later from his wounds. Eight bystanders, most of them children, were also wounded.
An angry crowd gathered outside Gaza City's Shifa Hospital after the attack, where the bodies were taken.
Islamic militant group Hamas, which is forming a government after winning Palestinian parliamentary elections in January, called the airstrike a "massacre". President Mahmoud Abbas said it was a "dangerous escalation" against the Palestinian people.
The unified condemnation was in sharp contrast to the first working session of the new Palestinian parliament, where Hamas legislators challenged Abbas by revoking all decisions made by the previous legislature at its final session last month.
"If the international community remains quiet the situation will explode," Hamas' Sami Abu Zuhri said.