Some of the mosques were in areas of Urumqi that saw street fighting earlier this week, after angry demonstrations by minority Muslim Uighurs sparked a crackdown by security forces and clashes with the Han Chinese majority that left at least 156 dead.

They included the White Mosque, one of the most popular places to worship in the large Uighur neighborhood of Er Dao Qiao. About 100 men argued with guards, demanding they be allowed in for prayers, a focal point of the week for Muslims.

A Uighur policeman guarding the mosque, who would not give his name, said: "We decided to open the mosque because so many people had gathered. We did not want an incident."

On Liberation Road near the White Mosque, a group of about 40 Uighur men and women began to march, shouting, crying and pumping their fists in the air as they walked.

Madina Ahtam, a woman in a multicolored headscarf, begged foreign reporters to stay with them as they walked.

"Every Uighur people are afraid," she said in English. "Do you understand? We are afraid. ... The problem? Police."

A group of 10 police in bulletproof vests and helmets and armed with batons and stun guns blocked their march within minutes, followed shortly by several dozen more police who surrounded the group and forced them to squat on the sidewalk. Police pushed journalists away from the area.

Kaishar, a 23-year-old car salesman, said his heart hurt when he first saw that the gates to the mosque were closed.

"There was no reason to shut the gate. They said it was for our safety but actually there is no need, nothing will happen here," said Kaishar, with a red prayer mat folded under his arm.

It was not known how many of the mosques across the city of 2.3 million people were opened.

A few blocks from the White mosque at the Yang Hang mosque, hundreds of men streamed in clutching green and red and blue prayer mats. A white notice that had been glued to the front gate canceling the day's service was gone.

An mosque official, who refused to give her name, had said earlier the closure was ordered for public safety reasons after the widespread ethnic violence between Uighurs (pronounced WEE-ger) and Han Chinese. She didn't elaborate.

The Government has imposed curfews and flooded the streets with security forces to avoid a repeat of the running street battles earlier in the week.

The secretary-general of the Urumqi Islamic Association, who would give only his surname Ma, denied there had been any order to shut the mosques and said individual mosques may have decided to do so independently.

But a man from the Urumqi Administration for Religious Affairs, who refused to give his name, said only mosques in areas not affected by the violence were told they could open.

"In the areas where there were serious clashes and violence, some mosques were closed for the safety of the religious people," he said.

Despite tight state control over Islam - imams are paid and vetted by the Government - there are too many mosques in Xinjiang to enforce a mass closure, said Barry Sautman, who specializes in China's ethnic politics at the Hong Kong University of Science and Technology. There are 23,000 mosques in Xinjiang, the highest mosque-to-Muslim ratio in the world, and that provides room for some anti-Goverment critics to slip through, said Sautman.

"It's impossible to control such an extensive number of religious personnel," Sautman said. In rural areas, he said, many officials in charge of religious affairs are Uighurs and are more sympathetic to Islam.

The violence in Urumqi (pronounced uh-ROOM-chee) began Sunday when Uighurs clashed with police while protesting the deaths of Uighur factory workers in a brawl in another part of the country.

The crowd then scattered throughout Urumqi, attacking Han Chinese, burning cars and smashing windows. Riot police tried to restore order, and officials said 156 people were killed and more than 1,100 were injured.

Other cities in Xinjiang, such as Kuqa, where bombs were set off before the Olympics last year, said mosques opened as normal.

The official Xinhua News Agency quoted the director of the Urumqi Civil Affairs Bureau, Wang Fengyun, as saying that families of innocent civilians killed in Sunday's riot would each receive 200,000 yuan (about $30,000) for each fatality.