A gun battle has erupted between Palestinian police loyal to Hamas and Fatah fighters at the main hospital in Gaza, killing one person and wounding eleven.

Witnesses and members of the rival factions said the fighting started at the entrance to the compound of the al-Shifa hospital in Gaza City.

Rival Palestinians also clashed outside the headquarters of the Fatah-controlled general intelligence agency in Gaza on Tuesday, a Palestinian security source said.

The source said the clash broke out when Hamas gunmen fired a rocket-propelled grenade at the agency's compound in northern Gaza.

The person killed in Tuesday's fighting was reported to be from the Hamas side. The victim has been identified as Ismail Abu al-Kheir.

A Fatah official told Al Jazeera that the ceasefire agreed on by the Hamas and Fatah in the Gaza Strip was still holding, despite the latest bloodshed.

The fighting at the hospital began when Hamas police tried to detain Fatah security men on suspicion they had been involved in earlier clashes.

The shooting, which lasted for nearly an hour, sent schoolchildren running for cover as they made their way to school. Rival fighters took up positions on rooftops, some firing rocket-propelled grenades at each other.

Contested plan

Clashes between Hamas and Fatah loyalists have broken out since Mahmoud Abbas, the Palestinian president and the head of Fatah, called at the weekend for early elections.

Hamas has rejected the call and accused Abbas of attempting to stage a coup.

As violence broke out after the Abbas announcement, both sides agreed to a ceasefire on Sunday.

The ceasefire stipulated, among other things, an end to all confrontation and the withdrawal of guns and fighters from the street.

The pact called for an end to incitement through the media, such as radio, and a stop to all demonstrations and rallies.

Israeli strike

Israeli forces meanwhile killed a Palestinian fighter and arrested two others in the West Bank city of Nablus.

The Israeli army said its troops identified a vehicle carrying the three wanted men, surrounded it and opened fire when the men attempted to escape.

Ala Anab, 24, of the Al Aqsa Martyrs Brigade, was killed by the fire, the group said.

PHOTO CAPTION

Palestinian Authority Prime Minister Ismail Haniyeh visits the mourning house of his bodyguard Abdul Rahman Nassar in Gaza City, Monday, Dec. 18, 2006. (AP)