GAZA, May 16: Hamas gunmen stormed the home of President Mahmoud Abbas's top security chief in Gaza and at least 16 people were killed in fierce factional fighting on Wednesday that pushed Palestinians closer to all-out civil war.

Palestinian officials said the widening hostilities could bring down a two-month-old unity government formed between ruling Hamas Islamists and Abbas's secular Fatah faction.

Fatah leaders said Abbas may declare a state of emergency, a move that could allow him to rule by decree for a limited period of time.

Hamas's raid on the home of Abbas security chief Rashid Abu Shbak came shortly after mortars struck near Abbas's Gaza office and gunmen attacked Hamas positions near the Interior Ministry.

In the deadliest single attack of the day, five detained Hamas gunmen, a Fatah escort and the Fatah driver were killed when their vehicle, travelling to a detention centre, came under fire from Hamas fighters, security officials said.

The shooting raised to at least 40 the number of Palestinians killed in factional fighting in the territory since a new round of violence began on Friday.

Terrified Gaza residents hid indoors as masked gunmen fought running battles street-to-street. Witnesses said militants were grabbing some civilians out of their cars to hold as hostages.

In one panicked call to a local radio station, a woman appealed to Abbas and Prime Minister Ismail Haniyeh of Hamas to act. “Do not leave us to die here,” she pleaded.

In addition to the five Hamas detainees who appeared to have been killed by accident by their own group, a Hamas member was “executed” by Fatah gunmen at a checkpoint, Hamas said.

Fatah said at least seven of its supporters were killed: Four guards at Abu Shbak's home, a member of Abbas's Presidential Guard and two member of pro-Fatah Preventive Security.

At least 16 Palestinians were killed on Tuesday, including two Hamas fighters. More than 100 have been injured since Friday, including a female nurse whose was caught in the crossfire.

Abu Qusai, a spokesman for Fatah's al-Aqsa Martyrs Brigades, called on Fatah ministers to resign. Under Palestinian law, that could end the government if independents followed suit.

Deputy Prime Minister Azzam al-Ahmad, a Fatah leader, said Abbas should declare a state of emergency. “We need such a step,” he said.

According to Palestinian law, Abbas can declare a state of emergency for 30 days, and that period cannot be extended without approval by two thirds of the Hamas-led legislature.

But Fatah officials have told senior Western diplomats that they believe Abbas could rule by decree for up to one year until new elections are held, according to Western officials.

Hamas blamed Fatah for the escalating violence, saying the attack on Abu Shbak's house came after his security guards opened fire on a passing Hamas patrol. —Reuters