Russian rescue workers rounded up on Saturday work at the site of a deadly attack on a Moscow-St. Petersburg train.
Russia's federal security chief earlier said that an explosive device equivalent to 7 kg of TNT caused Friday evening's deadly derailment. At least 26 people were killed and over 90 injured.
Traces of explosives have been found at the scene and prosecutors have opened a criminal case on charges of terrorism.
"We are concluding our search," Emergency Situations Minister Sergei Shoigu said.
In other developments, Russia's health minister said that the 18 people listed as missing after the attack had not been located in the three carriages that went off the rails. Rescue workers are assuming they independently left the scene of the crash.
Interior Minister Rashid Nurgaliyev issued on Saturday a description of one of the main suspects. He told journalists the suspect was "over 40, stocky and ginger-haired."
The announcement came after Russian Railways chief Vladimir Yakunin said that a second, weaker bomb had exploded on Saturday at 2:00 p.m. (11:00 GMT) at the site of the attack, but that it had not caused any injuries. The device went off as investigators were examining the area.
A similar derailment, also caused by a bomb, occurred on the same route in August 2007, injuring around 60 people. While two residents of the mainly Muslim North Caucasus region of Ingushetia were arrested in connection with that attack, prosecutors said it was planned by former soldier Pavel Kosolapov, a one-time associate of late Chechen warlord Shamil Basayev.
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.
MOSCOW, November 28 (RIA Novosti)
