Two people are reported missing and nearly 20 injured after an explosion in a Russian plant manufacturing TNT.

The blast took place Saturday in Dzerzhinsk, about 400 kilometers (250 miles) east of Moscow. The cause has not been determined.

Dmitry Krasnov, deputy governor of the region that includes Dzerzhinsk, said on state TV that two people were missing. The regional health ministry said 19 people were treated for injuries after the explosion; none of the injuries were considered severe.