Beijing has imposed tighter controls across Tibet as the biggest anti-Chinese demonstrations in nearly two decades begin to spread to more far-flung monasteries.

Two monks at Drepung monastery, on the edge of the capital, Lhasa, are reported to be in a serious condition after stabbing themselves in the chest, hands and wrists.

Radio Free Asia said Kalsang and Damchoe had refused to be taken to hospital and were in the monastery clinic. The apparent suicide attempt at the monastery where the protests began on Monday highlights the anger among Tibetans at Chinese repression and the exile of the Dalai Lama.

In Ganden monastery, a hilltop eyrie near Lhasa, the capital, monks had started a hunger strike to protest against the deployment of armed paramilitary police sent in on Wednesday to restore order. Across the border in northern India more than a 100 Tibetan exiles were dragged away by police, ending a march to their homeland to protest against China hosting the Olympic Games.

Indian officials, fearing that the march would embarrass China, banned the exiles from leaving the Kangra district that surrounds the city of Dharmsala, the headquarters of the Tibetan government-in-exile in India.

In Lhasa, senior officials called meetings of all government employees to remind Tibetans not to attempt to side with monks demonstrating for greater religious freedom before the Beijing Olympics in August and to show support for the Dalai Lama. Reading out a prepared document to staff, the leaders of work units outlined details of the protests that erupted on Monday with a march by 500 monks on the outskirts of the city.

One resident quoted the statement as saying: “These incidents pose a grave challenge to the long-term stability of Tibet.” The notice described the demonstrations as very serious.

All staff of government offices and state entities were banned from visiting religious institutions where unrest had erupted.

The government notice did not specify the punishment for defying the ban, but residents said it was unnecessary since Tibetans knew that the usual penalties were dismissal or withdrawal of salaries.

The demonstrations coincided with marches around the world to mark the 49th anniversary of an uprising against Chinese rule in the region. The Dalai Lama and many followers fled to India after it was crushed. Rights groups said that the protests had spread beyond the boundaries of Tibet proper into the large areas of China that are mainly populated by ethnic Tibetans.

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