It has had four other major mining accidents in the past that killed more than 130 workers.

In January 1986, an explosion at one of the northern plants killed 29 workers.

The blast killed two workers and a woman sleeping in her apartment.

The first was fatal when a sudden leak killed two workers.

He blew himself up in a bakery, killing three workers.

While attempting to break up the strike, officials killed three workers.

A fire at the new mill killed two workers and brought production to a halt.

In clashes with police were killed 6 workers, 13 are injured.

Wise killed the director, and three other white workers as well.

A series of explosions on 25 May 1917 killed 202 workers and wounded 689.