China's President Xi Jinping Monday ordered "vigilance and political sensitivity" in preventing safety hazards ahead of the party's centenary. A blast in the central province of Hubei killed 12 people Sunday.

Another 138 people were wounded - 37 severely - in the gas pipe explosion at a produce market in Hubei's Shiyan city Sunday morning.

It was the latest in a series of accidents resulting in many deaths and injuries. China demanded all-out efforts in rescues and for nationwide inspections against hidden risks.

An initial investigation has concluded that the blast was caused by a gas pipeline, according to cqcb.com, a news portal run by the Chongqing government.

China says at least 12 people are confirmed dead. The explosion tore through a crowded residential neighborhood in the city, it said Monday.

Rescue workers have taken dozens to hospitals but more are missing. The explosion reduced several buildings to rubble. Beijing News said the explosion also destroyed a vegetable market that was packed with morning shoppers.

"I heard a loud bang and immediately ducked under the table, thinking it was an earthquake," one of the victims told reporters.

Rescue workers continued to search Monday to find people believed to be trapped. Workers said they rescued at least 138 from the scene. About 40 suffered serious injuries.

The China Ministry of Emergency Management said it dispatched additional personnel to help search and rescue operations. Officials are still trying to determine the cause of the explosion.

The gas line explosion was one of the deadliest. It was similar to an explosion in the northeastern port city of Qingdao in 2013, which killed 55 people. The Qingdao explosion was caused by leaking underground pipelines.

The deadliest accident so far was a 2015 chemical plant explosion in Tianjin, which killed 173 people. Most of those killed were firefighters and police officers involved in search and rescue operations. The explosion was traced back to the illegal construction of storage facilities for volatile materials.

The accidents have ignited public demands for better safety standards and government enforcement. Some have called on the government to address the problem and ensure companies don't prioritize profits over safety.