HARBIN, June 2 (Xinhua) -- A forest fire that started Saturday morning on a nature reserve in northeast China's Heilongjiang Province was put out at around 8 p.m., according to the local forest fire prevention headquarters.

The forest fire, which broke out at around 9:30 a.m. on the Nanweng River Nature Reserve in the Greater Hinggan Mountains, had been extinguished as of 8 p.m. with the help of thousands of soldiers and rescuers, the headquarters said.

An initial investigation showed the fire was caused by a lightening strike, according to the headquarters.

No casualties have been reported.