One person has been rescued, and 18 others have been found dead following a coal mine accident in southwest China's Chongqing Municipality due to excessive levels of carbon monoxide, officials said on Saturday. 

The accident occurred at the Diaoshuidong coal mine at around 5 pm BJT on Friday in Chongqing's Yongchuan District. At the time of the accident, a total of 24 miners were working in the mine's underground tunnel face.

The mine has been suspended for more than two months, but the accident happened when miners were dismantling some equipment inside, local officials explained.

Live: Rescue work underway following a mine accident in SW China's Chongqing 

The cause of the accident is under investigation, and the Work Safety Committee of China's State Council will supervise the investigation.

The local police and fire departments lodged rescue efforts immediately as dozens of rescue vehicles stayed at the site all night for the rescue.

Diaoshuidong, built in 1975, is a high-gas coal mine with an annual production capacity of 120,000 tonnes. In 2013, three people were killed, and two others were injured in a hydrogen sulfide poisoning incident in the same mine.

The accident happened almost three months after another similar incident. In late September, 16 people were killed when high carbon monoxide levels trapped miners at Chongqing's Songzao coal mine.