Nepalese authorities jailed three Tibetan activists for three months for leading protests against China’s crackdown in Tibet, an official said Saturday.

Katmandu district chief administrator Jaya Mukunda Khanal said the three were arrested Thursday for violating the Public Security Act and will be kept behind bars for 90 days.

They were the first among Tibetan refugees in Nepal sentenced to jail terms since March, when almost-daily protests started to condemn China’s crackdown in the Himalayan region in front of the Chinese Embassy and United Nations offices in Katmandu.

Khanal identified the Tibetans as Kelsang Chung, Ngawang Sangmo and Tashi Dolma.

China says 22 people died in anti-government violence in Tibet’s capital Lhasa in March, while foreign Tibet supporters say many times that number were killed in the protests and a subsequent crackdown.

Nepalese police have been breaking up the rallies and _ until now _ only briefly detained protesters before letting them go.

Authorities have banned protests by the Tibetan exiles, saying demonstrations against friendly nations, including China, will not be allowed. Tibetan refugees have also been barred from all political activities.

The United Nations and international rights groups have criticized Nepal for using what they say is excessive force to stop the protests. Police have beaten people with batons and dragged them through the streets while detaining them.

Thousand of Tibetans were allowed to live in Nepal or pass through on their way from Tibet to Dharmasala in India, where Tibetan spiritual leaders live in exile.