OCCUPIED JERUSALEM, 20 December — The Palestinian Authority, asserting its authority, launched a crackdown against the Hamas group and arrested 15 of its own security officers in the southern Gaza Strip who refused to respect a cease-fire with Israel.

Palestinian sources said the PA had also dismissed about 15 other security officers in the southern strip who had been active in the Palestinian popular resistance movement in Khan Younis area.

It was the first time the PA had ordered police arrested for their part in anti-Israel attacks. The move came amid continuing Palestinian efforts to crack down on militants. As part of the efforts, the PA also closed six offices of the Hamas in the Gaza Strip earlier.

Last night, Palestinian police shut down five mortar bomb factories run by activists in the Jabaliya refugee camp outside Gaza City, witnesses said.

The police stormed a metal workshop, which secretly produced mortars, run by people close to Hamas, they said.

The PA says it has arrested more than 180 activists in December and has shut nearly 40 offices linked to Hamas and Islamic Jihad since the weekend.

A senior Hamas leader in the West Bank said yesterday the Palestinian group was considering suspending attacks against Israel. "Hamas is studying the issue of suspending attacks," Sheikh Hassan Youssef told Reuters. "It has not been decided yet, but the movement is aware of the interests of the Palestinian people and will take a decision that stems from their higher interests."

It was the first time that a leader of the group said it was considering halting such attacks since Palestinian President Yasser Arafat called in a speech on Sunday for an end to armed conflict with Israel.

Pro-Hamas website www.palestine-info.com, which carries the movement’s statements, said no decision had been made on suspending attacks and denied at this time there was any intention to do so.

"Hamas denies intentions to stop armed attacks against the Zionist entity and promises to continue armed resistance until the removal of the occupation," a statement attributed to a senior Hamas source said on the website.

Senior Hamas officials in Gaza said earlier they knew nothing of any move by the group to suspend attacks. Youssef also said there was no decision or statement yet.

Marwan Barghouthi, the West Bank leader of Arafat’s Fatah faction, told Reuters that Palestinian factions were "reconsidering means and ways of resisting occupation, particularly martyrdom attacks."

Hamas officials had said after Arafat’s speech that resistance to Israeli occupation was still a legitimate pursuit.