BEIJING, May 21(Xinhuanet)-- The Ministry of Agriculture announced here Saturday that the reported death of migratory birds in West China's Qinghai Province was caused by bird flu.

The ministry said the national bird flu reference laboratory confirmed that the latest death of migratory birds in Gangcha City of Qinghai Province reported on May 4 was caused by the deadly H5N1 virus.

The disease did not spread to human kind and fowl, the ministry said.

It said Qinghai had taken emergency measures by closing off the spots to prevent people and fowl from contacting wild birds. Quarantine measures have also been adopted.