Local officials in central China's Hunan Province have covered up nearly half of the casualties in a fireworks factory blast that actually claimed 13 lives, China's Ministry of Emergency Management revealed on Monday.

According to the emergency management authority, the workplace safety commission of the State Council recently summoned the leading city officials of Changsha and Liuyang in Hunan Province, admonishing them to reflect on the underlying problems revealed by the accident and enhance the safe production of fireworks.

Previous reports said the explosion on December 4 killed seven people and injured 13. The investigation launched by local government confirmed six other deaths following the incident.

As of Tuesday, 10 suspects involved in this case have been placed under "criminal compulsory measures" while four local officials have been detained and another three suspended. 

Read more: Fireworks factory blast kills 7, injures 13 in central China