The death toll in a suicide bombing on a train in southern Russia that authorities blame on Chechen rebels has reached at least 42. More than 200 people were also reported injured in the incident.
Russian authorities say they suspect Chechen rebels are to blame for the blast on a commuter train in a region close to Chechnya.
The head of the Federal Security Service says three women and one man carried out the attack, which left one of the train carriages cut in two.
Investigators said they found the remains of the man with grenades still strapped to his legs. Two of the women apparently jumped from the train just before the explosion, while the third was seriously injured.
The blast came two days before Russia holds its parliamentary elections. President Vladimir Putin denounced the bombing as an attempt to destabilize the country on the eve of the vote.
About 150 people have died in bombings blamed on Chechen separatists this year. Most have occurred near the breakaway region where separatists have battled Russian troops for most of the last decade.
The Kremlin says the conflict is part of the larger war on terrorism, and has resisted calls from most foreign governments to seek a political solution.