The death toll from a gas leak at a steel plant in north China has risen to 21, after executives admitted they had covered up the true scale of the accident, state media said on Friday.
When the gas leak occurred at the Puyang Iron and Steel Co in Hebei province on Monday, officials initially said that only seven workers were killed, Xinhua news agency said, citing local authorities.
But company executives confessed Thursday that they had covered up the death toll during questioning by a joint investigative group made up of police and work safety officials, the report said.
The deputy manager of the plant was subsequently arrested and two other factory officials placed under house arrest for the alleged cover-up, it said.
The gas leak occurred as workers were assembling a furnace, it added.
China's work safety record is notoriously bad, with thousands of people dying every year in mines, factories and on construction sites, according to official tallies.
In northwest Gansu province, five people were missing after a huge explosion at a chemical plant belonging to state-run China National Petroleum Corporation on Thursday, Xinhua said. Previous reports put the death toll at two.
Also on Thursday, more than 150 workers at an electrical factory in southern Guangdong province tested positive for suspected mercury poisoning stemming from lax work safety regulations, reports said.