Two people are reportedly killed and another is in critical condition after poisonous gas leaked in a factory in northwest China Saturday morning.

The China National Radio reported that the factory was located in Haidong of Northwest China's Qinghai province, near a highway linking Pingan and Hualong.

Several rescue personnel have arrived at the scene, including police, firefighters, medics and work safety watchdogs. Firemen in protective gear are looking for those trapped inside the factory.