A forest fire that broke out Tuesday evening in the northeast province of Heilongjiang has been put out, according to the provincial forest fire prevention headquarters. The fire ignited around 7:06 p.m. at the Shilihe Forest Farm under the jurisdiction of the Hegang Municipal Forestry Bureau. Two helicopters, three planes and 2,335 firefighters and volunteers brought the fire under control on Wednesday night. The cause of the fire remains under investigation. The wildfire was the third to hit Heilongjiang in recent days. Last Saturday night, firefighters put out a forest fire that raged for a full day in the city of Heihe. On Sunday, a grassland fire in the city of Yichun forced the evacuation of 465 residents. The frequent occurrence of wildfires prompted national forest fire prevention authorities to issue an orange alert on Sunday for the Inner Mongolia Autonomous Region and Heilongjiang. Orange is the second-highest alert level in China\'s forest fire prevention system.