Volunteers without specific training are encouraged not to jump into disaster centers and should save their efforts for post-disaster recovery, an expert said.

They were also urged to protect themselves and learn self-help tips, after a volunteer was killed by a fallen rock on a road linking Gaohe town and Longmen county on Monday.

Tian Feng, a disaster relief specialist with Conservation International, said: "What most of these people don't realize is that spontaneous volunteers without specific training and no affiliation can actually cause more problems than they alleviate in a disaster situation."