Over one-hundred people were killed in a large explosion at the Huainan Forced Labor Camp in southeast China’s Huainan City in Anhui Province. The explosion occurred at 10:30 p.m. on Nov 11, according to the Information Center for Human Rights & Democracy in Hong Kong.

The cause of the explosion is still unknown, but hundreds of police and armed police sealed off the site.

The information center disclosed that the labor camp has five groups of detainees totalling up to 1,000 people. This is a coal mine and gravel production operation, which would stock large amounts of explosives.

The explosion was big enough to shake residents within five kilometres of the site.

According to the Huainan municipal government, the incomplete death toll report indicates that over one-hundred people died in the explosion.