Two female suicide bombers blew themselves up at an outdoor rock concert north of Moscow Saturday, killing at least 14 people around them and injuring about 60 others.

The interior minister said it appears that Chechen rebels planned the attack. The Chechens, however, denied the government's allegations.

Up to 40,000 spectators had gathered for the rock festival at Tushino airfield when two explosions went off at two different gates into the event.

Police sources said the first explosion occurred after guards stopped a woman at the gate into the festival and she detonated a belt of explosives.

After the explosion, police directed the audience to leave through a different set of gates, where the second explosion took place.

Both were wearing explosive belts packed with nails and ball bearings. People standing next to them when the bombs went off suffered severe burns and shrapnel wounds.

Moscow city police spokesman Valery Gribakin said 16 people were killed in the explosions, including the two female bombers.

News reports said a passport found at the site identified one of them as Chechen.

The rock festival, called "Krylya," Russian for "wings," is a popular summer event held at the Tushino airfield north of the city.

Fears of terrorism have been high in Moscow since last October, when Chechen rebels seized a theatre in the city and held 800 people hostage for days.

At least 129 of the hostages died when Russian special forces flooded the theatre with a narcotic gas and stormed in.