A senior leader of Hamas's military wing was killed in an Israeli missile strike on his car as it drove through a Hamas stronghold in the Gaza Strip on Sunday, witnesses said.

The missile, which witnesses said was fired by an airforce drone, ripped through a car carrying a senior field commander of Hamas's Izz el-Deen al-Qassam brigades, Khaled Abu Selniya, 33. He was killed and six passersby were wounded.

Hamas vowed to avenge the death of Selniya, whom it described as a senior field commander of the group's armed wing, which has been behind scores of suicide bombings and other attacks against Israel over the past decade.

"It was a clear assassination of one of our mujahideen (Muslim fighter) ... Hamas will be able and capable of teaching the enemy a painful lesson," said Mushir al-Masri, a Hamas spokesman.

The Israeli army said in a statement that Selniya was targeted by the airforce because he played a central role in the manufacture and development of Qassam rockets which Hamas militants have fired at the nearby Israeli city of Sderot.

Selniya's mangled body was taken to a local hospital. Charred wreckage from the car was strewn across the street and windows were shattered in nearby shops.

The strike took place shortly after Hamas militants celebrated in the streets at the release of another leader of the group by Palestinian security forces.

The leader had been arrested earlier in the day and Selniya was apparently returning after visiting the man in his home in Gaza City's Sheikh Radwan neighborhood.

"There was an airforce strike on a senior Hamas terrorist who was traveling in a car," an army spokeswoman said.

Witnesses said an Israeli military drone was flying overhead when the car burst into flames. Several witnesses reported seeing a flash of light in the sky before the explosion.

"Your blood will not be in vain. We will get revenge," Hamas activists shouted over loudspeakers in the Gaza Strip.

Israel has killed scores of Palestinian militants in air strikes since a four-year-old Palestinian uprising began.

Israel's policy of targeting militants has been condemned by human rights groups and many members of the international community.

Israel says it is the only way of reaching militants who hide in civilian areas without causing heavy civilian casualties.

Tension has escalated in Gaza since Prime Minister Ariel Sharon announced his plan to withdraw troops and settlers by the end of next year from the narrow coastal strip captured by Israel in the 1967 Middle East war.

Islamic militants hope to make the army withdraw under fire, while the military is determined to crush Hamas and other militant groups opposed to its existence to ensure that the pullout will not be seen as a victory.

(China Daily via agencies September 20, 2004)