An explosion that killed 11 people in China last week was caused by a disgruntled coal mine.
The blast on a commuter bus was initially believed to be an accident; however investigations have revealed the culprit, according Zeenews.com.
It is not yet known why the man, a coal miner named Gao Wanfeng, set off the blast, although it is reported that he did have disputes with his mine owner last year regarding injury compensation.
Gao is believed to have died in the explosion.
An additional forty people were also injured in the blast.