By Jane Macartney

BEIJING, May 23, 1996 (Reuter) - Tibet on Thursday marked the 45th anniversary of an accord with Beijing on the region's "liberation" by the ruling Communist Party.

The anniversary coincided with officials entering monasteries to try to put down anti-Chinese unrest.

A campaign launched this month to strip all pictures of the Himalayan region's exiled god-king, the Dalai Lama, from monasteries and temples as well as offices, schools and homes has sparked anger among Tibet's lamas, residents have said.

A lengthy commentary in the party mouthpiece the People's Daily hailed the May 23, 1951 signing of an accord between the central government in Beijing and the regional Tibet government on the "peaceful liberation" of Tibet.

The 17-clause agreement "returned (Tibet) to the embrace of the great family of the motherland and opened the way for the Tibetan people to leave dark suffering and enter a bright new age of happiness," the commentary said.

The People's Liberation Army entered Tibet in 1951 and marched into the capital, Lhasa, in August of that year.

Only under socialism could Tibet develop and only under socialism "can the motherland really effect equality of its peoples," the commentary stressed.

Renewed unrest has broken out in the region following fresh attempts by officials to enforce a ban on the display of pictures of the Dalai Lama, who in 1989 won the Nobel Peace Prize for his peaceful struggle for more autonomy for Tibet.

An official of the Tibet Religious Affairs Bureau said the 15th-century mountain-top Ganden monastery, closed on May 6 after a violent clash between lamas and a work team sent to implement the ban, would remain sealed off for at least two to three months.

"The work team is now educating the monks in the Ganden monastery," the official said in a telephone interview. "These lamas are young, they come from remote areas and are less educated. So the work team must teach them."

Many of the monastery's 700 monks had left, he said.

It was not clear if they had left voluntarily after the clash in which several monks were reported to have been detained and at least two were hurt at the monastery, some 40 km (24 miles) east of Lhasa.

Other monasteries and temples in and around Lhasa that closed after that clash had reopened last week, the official said.

Authorities have ordered all work units in Lhasa to report on the results of a check on the display of Dalai Lama portraits before May 25, one factory official said by telephone.

"In our factory, we began mobilisation meetings on May 6 and made spot checks in workers' homes in the afternoon and found that 80-90 percent of worker's families don't hang pictures of the Dalai Lama," he said.

"So far as I know, almost all units have completed their mission successfully," he said.

The tough crackdown on images of the man Beijing blames for inciting anti-Chinese unrest in the Himalayan region followed signs that pro-independence activists have taken to more violent means, including bombings, to back their campaign.

The Dalai Lama fled into exile in 1959 after an abortive uprising against Chinese rule. Beijing accuses him of encouraging Tibetan independence from his home in India and stirring up anti-Chinese sentiment to try to split China.

Pictures of the Dalai Lama had been allowed in Tibet since 1979 as part of a Chinese decision to allow religious freedom.

Beijing's tolerance of support for the Dalai Lama has been strained since last year when he identified an alternative choice to that of China's as the reincarnated Panchen Lama, Tibetan Buddhism's second most important spiritual leader.