Several rockets were found hidden not far from one of Moscow'a principal airports late Thursday, RTR television reported quoting security forces.
They were found in a cemetery a few kilometres (miles) from Vnukovo airport to the southwest of the Russian capital.
The rockets, with a range of three kilometres (two miles), are designed for helicopter-mounted rocket launchers but can also be fired from the ground, which might imply that a terrorist act was being prepared against a plane, the sources said.
But they might also have been stolen from the army and sold to a criminal gang for use in clan warfare, they added.
The dump was found close to where a young woman was badly burned in the face last week by an explosion as she tried to rip down an anti-Semitic slogan.