BEIJING (AP) — Seventeen coal miners have died after being trapped by a weekend gas explosion in northwestern China.

The official Xinhua (shihn-wah) news agency reports that the miners were trapped Saturday by the blast at a mine 70 miles from Urumqi, the capital of the Xinjiang (shihn-jahng) region.

Three other people working inside the mine were rescued.

The cause of the explosion is under investigation.

China has the world’s deadliest mines, although the safety record has improved as regulators strengthen enforcement of safety rules.

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