Qinghai-Tibet Railway, the world's most elevated railway, was not affected by the two earthquakes that hit the border of Qinghai Province and Tibet Autonomous Region early on Monday.

"Railway traffic was unaffected, even part of the railway is in the quake area," said Xu Chuanjie, an official with the Qinghai provincial earthquake administration.

The Amdo Station in Tibet's Amdo County, the nearest railway station to the quake area, reported nothing abnormal after the quakes, and a train passed on schedule at 3:02 a.m.

A 5.0-magnitude quake struck at 1:56 a.m. at the Mongolian-Tibetan Autonomous Prefecture of Haixi in the west of Qinghai, and another one measuring 4.0 on the Richter scale hit the same area at 5:44 a.m.

No casualties or damages have been reported after the quakes.