A female passenger was seized by police on Tuesday after she deliberately released methane gas in a Beijing subway station, the Beijing-based Qianlong.com has reported.

Several passengers were choked by the irritating gas on Tuesday morning as they passed a metro exit at the Dongzhimen station on subway Line 2.

An employee of the subway service hotline said the gas was methane.

The passenger carrying the methane was blocked by workers at the station before she released it into the air.

The incident didn't cause a panic, and the amount of gas was so small that it didn't pose a health threat to passengers.