BEIJING - Beijing will clear out subterranean hotels in old air-raid shelters near venues for the Olympic Games, fearing fallout from potential accidents at the guesthouses.

The Chinese capital built dozens of air-raid shelters in the decades since 1950s.

Many still exist today, ranging from small basement rooms to vast underground tunnels hundreds of metres long, and some provide budget lodgings for migrant workers and other cash-strapped visitors to the city.

"There are 70,000 or 80,000 people living in these (shelters). Some small guesthouses have up to 100 to 200 people," Thursday's Beijing News quoted Li Changshuan, head of Beijing's Civil Defence bureau, as saying.

"The rooms are small and narrow, and have latent safety issues," Li said.

Li said any such guesthouses near areas that athletes would travel through or use during the Games would be "gradually cleared out and no longer offered for rent".

Authorities had already "rectified" underground offices in the shelters over an eight-month campaign, removing many hidden dangers and banning their commercial use, Li said.

Beijing has moved to clamp down on the sale of underground housing, whose cheap asking prices and rents have thousands of people living in poorly ventilated fire-traps under common apartment blocks.