A blast tore through a bus stop on Wednesday near Moscow's training center for the Federal Security Service, injuring no one, police and the National Anti-Terrorism Committee said.
"An unidentified explosive device blew up at a bus stop at about 4:30 p.m.," said Nikolai Sintsov, spokesman for the National Anti-Terrorism Committee.
A police spokesman confirmed that there were no casualties from the explosion near the FSB Academy on Michurinsky Prospekt, in the vicinity of the Universitet metro station in southern Moscow.
An unidentified FSB official told Interfax that the explosive was planted by Islamist militants from the North Caucasus.
Interfax, citing the National Anti-Terrorism Committee, said there was some damage to cars near the bus stop.
"A team of experts from the Federal Security Service is working at the scene. All possible theories are being considered," the committee said in a statement carried by Interfax.
(Reuters, MT, AP)