Thirty-three workers were killed after a gas explosion at a coal mine in China's northern Shanxi province, officials said on Friday.

Seventy-one miners were in the shaft when the blast occurred on Thursday.

Twenty-eight miners were killed in the initial explosion and five others died during a rescue attempt.

The accident comes two weeks after 166 people were killed in a coal mine in neighbouring Shaanxi province in the country's worst mining disaster in 44 years.

A gas explosion in October killed 148 miners in central Henan province.