Updated 10:35 p.m. ET with adjusted totals
A gas explosion at a coal mine in China has killed 13 miners, and another 20 miners are missing and presumably trapped underground, Chinese state media report. The Xinhua news agency had previously given totals of 15 dead and 18 missing.
According to Xinhua, more than 200 rescue workers were at the rural mine near the city of Chongqing, looking for any survivors.
The explosion hit Monday morning, NPR's Rob Schmitz says, when 35 miners were working. Two of them escaped.
"An investigation is underway into the cause of the accident," Rob says. "Last month, a gas explosion in a coal mine in northwestern China killed 20 miners. A preliminary investigation has found that accident was caused by illegal mining."