A team of mainly-Tibetan police experienced in working at high altitudes Wednesday arrived in Yushu to help provide security in the quake zone of northwest China's Qinghai Province.

The 55-member team, all from mountainous Aba Tibetan and Qiang Autonomous Prefecture of neighboring Sichuan Province, would be deployed on security and traffic duties, said Wang Yunzhong, a publicity official of Sichuan Provincial Department of Public Security.

"The team are experienced in working at high altitudes and most of them are Tibetans," Wang said.

Most of the population in the quake-hit Yushu area, which has an average altitude of about 4,000 meters, is also Tibetan.

"Our team can handle both the plateau area and the language, which will make it much easier to do our job here," Wang said.

Rescuers from all over China have been suffering altitude sickness in Yushu over the past week, with symptoms of dizziness, vomiting and passing out.

The altitude sickness had forced at least 200 rescuers to leave Yushu, a senior resuce official said Saturday.