A massive fire broke out early Sunday after an explosion on a gas pipeline in the southwest of Moscow, sending flames over 200 metres (600 feet) into the sky, Russian news agencies reported.

Several people are reported to have been injured. More than 35 fire-fighting teams were sent to the scene.

The authorities have shut off the gas supply to the area and are investigating the cause of the blast.

Moscow Mayor Yuri Luzhkov, who rushed to the scene, said that five people had been injured in the fire, including one man who received burns on 35 percent of his body, but there had been no fatalities, the Interfax news agency reported.

The mayor believes the explosion was caused by technical problems.

"I am 99 percent sure that it's a techogenic disaster," the mayor said.

Moscow First Deputy Mayor Pyotr Biryukov said the fire was the worst to hit Moscow in decades.