A car packed with explosives and weapons was intercepted on Thursday near a railway station in Karelia, northwest Russia, a police official said.
Northwest Russia's acting police chief Vadim Kashirin said the car was detained near the city of Petrozavodsk by station security.
He did not provide any other details of the incident.
Russian President Dmitry Medvedev on Wednesday ordered action to prevent terror attacks on Russia's railways, in particular heightening security arrangements and setting tight deadlines for investigating such incidents.
The high-speed Nevsky Express train derailed last Friday killing 26 people and injuring over 90 en route from Moscow to St. Petersburg after a bomb equivalent to 7 kg (15 lbs) of TNT detonated on the track. A second, weaker bomb exploded at the site on Saturday, and is believed to have targeted investigators.
The blast has raised fears of a resurge of terrorist attacks in the Russian capital and other major cities. Russia was hit hard by terrorism in the 1990s and the early years of this decade, but violence has largely been confined to the volatile North Caucasus region since 2004.
ST. PETERSBURG, December 3 (RIA Novosti)