At least 15 people have been confirmed dead in a series of gas explosions in the southern Taiwanese city of Kaohsiung.

"The gas explosions on Thursday night killed 15 people and injured 233 others," Kaohsiung's mayor Chen Chu told reporters.

A report by Chinese news agency Xinhua said that before the explosion, smoke with a "gas-like smell" was seen coming out of drains in the streets.

The blast caused big fires and overturned cars, it added.             

The damage was spread across several streets of the city, Xinhua said.