GAZA CITY, Gaza Strip (AP) – Thousands of police loyal to moderate Palestinian President Mahmoud Abbas marched in a show of force Thursday, a day after the Hamas-led government deployed 3,000 heavily armed militants in a daring challenge.

Abbas, who has been wrangling with Hamas over control of the security forces, demanded that the government take the new militia off the streets immediately, Abbas adviser Saeb Erekat said. However, Prime Minister Ismail Haniyeh of Hamas said the unit is legal and suggested it would not be disbanded.

There were no signs that Palestinian police, dominated by supporters of Abbas’ Fatah Party, were getting ready to take on the Hamas unit. In Thursday’s march, clapping and whistling police chanted “Jerusalem! The president! The homeland!” as they walked past Hamas gunmen. Neither side made a move.

Tensions also escalated in the West Bank, where a senior Hamas politician, Deputy Prime Minister Nasser Shaer, cut short a meeting after Fatah gunmen surrounded an office building and fired into the air. Shaer later left town under heavy police escort.

The unprecedented Hamas-Fatah friction, including deadly drive-by ambushes against two Hamas gunmen in Gaza earlier this week, came amid new efforts to explore a possible revival of Mideast peace talks.

Abbas was to hold talks Sunday with Israeli Foreign Minister Tzipi Livni, the first high-level meeting since Hamas came to power in March, Erekat said. Israel has said it would not resume negotiations, even with Abbas, unless Hamas softens its violently anti-Israel views.

Without a Hamas about-turn by year’s end, Israel plans to begin drawing its final borders with the Palestinians under Israeli Prime Minister Ehud Olmert’s “consolidation plan.”

Olmert was to make his first trip to Washington as prime minister next week and was expected to face U.S. pressure to negotiate a deal with Abbas rather than move unilaterally.

Israel could present the Abbas-Livni meeting to its Washington hosts as a goodwill gesture. The meeting is to take place in the Egyptian resort of Sharm-el-Sheik, on the sidelines of the World Economic Forum, an international gathering of business leaders. Israeli officials said Livni’s schedule has not been finalized, but a meeting was possible.

Also Thursday, Palestinian militants in the Gaza Strip fired rockets toward Israel, with one landing near an army base, the military said. No injuries or damages were reported. Palestinian militants frequently fire the rockets, but they rarely cause casualties.

Abbas’ most pressing problem Thursday was the intensifying Hamas-Fatah conflict.

Since Hamas came to power, Abbas has tried to keep the Islamic militants in check by expanding his considerable powers, in part by asserting control over all six branches of the security forces. In a counter move, Hamas formed a 3,000-strong militia, consisting mainly of members of its military wing, Izzedine al Qassam.

Interior Minister Said Siyam of Hamas deployed the unit Wednesday, defying Abbas’ orders that it be disbanded. Hamas militants armed with assault rifles, grenades and anti-tank missiles took up positions in the streets, and in one case put down a peaceful protest by college graduates seeking teaching jobs.

On Thursday, the Fatah-dominated security forces responded. About 1,000 marched through the streets, chanting: “We are the authority! We salute Abu Mazen (Abbas)!”

The shirtless policemen ran through the streets and conducted drills near Hamas patrols. The policemen were unarmed, but were followed by commanders in jeeps, their weapons raised in the air.

Gen. Suleiman Hilles, commander of Palestinian security forces in the West Bank and Gaza, said the forces were deployed to send a message that “the Palestinian police is the only side that can maintain law and order.”

However, the lines were not clearly drawn, since some of the police officers also back Hamas. Several hundred police officers met Thursday with Haniyeh and professed their loyalty to the government. Haniyeh told the officers that the new unit of militants was formed legally and would work alongside the security forces.

Ahmed Shaaban, 32, a captain in the Palestinian police, disagreed.

“We don’t want to see this militia in the streets,” he told a reporter. “I don’t want my children to grow up in a country protected by militias.”

Taxi driver Musleh Abu Aita, 38, said the Hamas gunmen should stick to attacking Israel and not get involved in crime-fighting.

“I am not going to obey them, not because I don’t like them, but because this is not their business,” he said.

Hamas gunmen refused to talk to reporters, saying they were given instructions not to speak.