BEIJING -- The Supreme People's Procuratorate announced Tuesday that it has sent staff to investigate a coal mine explosion that killed 32 people Saturday in northern China's Inner Mongolia autonomous region.

The explosion around midday Saturday at Baoma Mining Company in the city of Chifeng occurred when a total of 181 people were working underground. A total of 149 managed to get above ground to safety.

The Supreme People's Procuratorat said it is investigating the case in collaboration with local procuratorates.

Several officials have been suspended from their duties after the explosion, and those in charge of the coal mine have been detained by police.