The incident involved oxygen gas tanks that exploded at the mine in the Mazowe area, around 40 kilometres (25 miles) northeast of the capital Harare.

"We confirm that six foreigners died," said police spokesman Paul Nyathi told AFP, adding investigations were underway.

But a local MP said the death toll was eight, including two Zimbabweans, in two accidents that occurred on Thursday and Friday.

"There were two explosions on two different days," local lawmaker Fortune Chasi told AFP on the phone after returning from the scene.

On Thursday night, an oxygen tank blew up as Chinese employees were working on it, he said.

"It killed six of them, with another local employee," he said.

The following day, a 21-year-old Zimbabwean worker was killed as he "tried to open an oxygen gas tank... and it just blew up," Chasi said.