Russian police have detained 15 Islamist extremists and seized a stash of weapons and explosives in an overnight raid in Moscow.

The Interior Ministry said that the suspects were members of Takfir Wal-Hijra, a radical Islamist group originally formed in Egypt.

The ministry said the cell was exposed "during the course of investigative measures into common criminal cases," the Voice of Russia reported.

"Funds received from committing common crimes were used to finance this organisation," a Ministry spokesman said.

Fourteen members were arrested as police stormed a number of flats in eastern Moscow. Hand grenades, bombs, guns and ammunitions were found.

"The search of the residences of organisation members yielded three homemade bombs with detonators and shrapnel elements, one of them made to be fastened with a belt, bomb parts, including detonators and fuses, handguns, grenades, cartridges and extremist literature," a ministry spokesman said.

The 15th suspect was arrested in a separate raid at another location.

Takfir Wal-Hijra was founded in Egypt in 1970 and was banned for "inciting inter-ethnic and inter-religious enmity" in Russia in 2010.

Russia, which is about to host the Winter Olympics in the southern town of Sochi, has been facing a decade-long Islamic insurgency in the northern Caucasus.

Religious violence in the regions of Ingushetia, Dagestan and Chechnya has spilled over into other Russian regions including Moscow in the past.

A female suicide bomber killed six people on a Volgograd bus in October.