BEIJING- A freak blizzard and sand storm killed 15 explorers in mountainous remote northwest China on Friday, the Xinhua news agency said on Monday.

More than 70 explorers, hired by a company connected to oil giant China National Petroleum Corp., were working in Haixi prefecture in Qinghai province, bordering Tibet, when they were hit by a "heavy snowstorm, rainstorm and sandstorm simultaneously", Xinhua said.

"Fifteen explorers were found dead and 13 others injured in the snowstorm which was unlikely to happen once in a century," an unnamed local official was quoted as saying.

Rescue and investigation efforts were continuing, Xinhua said.