Palestinian police officers guard the area around a bloodstain where former Palestinian security chief Moussa Arafat was shot and killed

Palestinian gunmen shot and killed the former Gaza security chief early Wednesday, an incident sure to heighten fears about growing lawlessness in Gaza. the shooting comes as Israel prepares to pull its last remaining troops out of Gaza by the middle of the month.

Gunmen with automatic rifles and anti-tank grenades stormed the house of former Gaza security chief, Major-General Moussa Arafat, fought for over 30 minutes with his security guards, then dragged him out into the street and shot him dead.

General Arafat, a cousin of the late Palestinian leader Yasser Arafat, is the most senior public figure killed in what is widely seen as growing internal chaos and lawlessness in Gaza.

The Popular Resistance Committees claimed responsibility for the assassination, saying it did so as punishment for alleged corruption and earlier attacks against Palestinian militants.

The Resistance Committees is a violent coalition, made up mostly of former members of the mainstream Fatah movement of President Mahmoud Abbas.

President Abbas condemned the assassination, vowed the killers would be tracked down and brought to justice and put Palestinian security forces on high alert.

Palestinian politician and human rights activist, Mustafa Barghouti said Wednesday's shooting was a challenge to the Abbas government.

Mr. Barghouti said the disarray of the Palestinian security services is largely to blame for the current chaos. He said the President must move to re-establish law and order and should strengthen the legal system to do so.

Similar warnings were echoed by Israeli Foreign Minister Silvan Shalom.

Mr. Shalom said it's time for President Abbas to wake up and make the right strategic decision to start collecting illegal weapons and to disarm and dismantle the terrorist organizations.

Mr. Shalom said Israel had seen no indication so far that the Palestinian leader is willing to take tough action against the militants.

Concern is also growing that the Palestinian Authority is too weak and its security forces too fractured and disorganized and mount any effective action against militant groups - be they the Popular Resistance Committees or Islamic groups such as Hamas.