BEIJING Sept 19 (AP) -- Chinese police arrested at least five monks and beat two of them severely after posters calling for Tibetan independence appeared in southern Gansu province, a report said today. Gansu, in far western China, was formerly part of Tibet and is inhabited by ethnic Tibetans.

The posters appeared in March at Labrang Monastery, an important center of Tibetan Buddhism, and in a neighboring area, the London-based Tibet Information Network reported, citing sources in the area. Surveillance at the monastery has been increased, the report said. Among those reported arrested was Jigme Gyatso, a monk who was beaten so severely he showed signs of brain damage and could not move his arms or legs, said the Tibet research group. It said he was released only after his parents paid 1,000 yuan, the equivalent of $120.

Another monk also was badly beaten and is still in prison, the report said. Two other monks also were arrested, and a third is missing and believed to be in police custody, it said.

Drolkar Gyap, a 26-year-old ethnic Tibetan man from the region, was detained in May and sentenced to seven years in prison for a political offense, the report said. Details of the alleged offense were not available.

Last week, the Liberation Army Daily reported large-scale military exercises in Gansu this month.

China says Tibet has been part of its territory for centuries. Many Tibetans say they have enjoyed de facto independence much of that time.