A rubbish dump landslide in the Sri Lankan capital Colombo killed at least six and injured 11, hospital sources said on Friday, as emergency workers dug into the mountain of trash to save survivors buried in dozens of houses.

Fire fighters fought to extinguish a fire at the top of the estimated 300-foot (91 metre) rubbish dump which had collapsed after the flames engulfed it. Witnesses told Reuters that at least 40 houses may have been buried in the landslide.

A 13-year-old boy, and two girls aged 14 and 15, were among the six who had died, Pushpa Soysa, head nurse at the main Colombo hospital, told Reuters.

"Ten more are being treated at the hospital," Soysa said.

The government deployed troops and police to help with the rescue operation on the island nation's traditional new year's day.

Police said in a statement they were unable to say how many houses had been buried in the landslide.

"It is too early and still we can't say how many houses are damaged or destroyed and how many people affected," Pradeep Kodippili, Disaster Management Centre spokesman, said.

Residents in the area have been demanding the removal of the dump saying it was causing health issues. The government had planned to remove it soon under an infrastructure plan.