The bus was seized Tuesday morning in the Stavropol region, neighboring rebel Chechnya, by a gunman who demanded the release of five Chechens jailed for a previous hijacking. After a daylong standoff, a Russian commando squad rushed the bus in a lightning raid, killing the hijacker and freeing the hostages.
The swift, coordinated action was praised by President Vladimir Putin and the leaders of the Federal Security Service. But the hijacking also underlined Russia's inability to ensure safety in the restive area near Chechnya.
On Wednesday morning, a bomb exploded on a bridge in the nearby town of Cherkessk, the Emergency Situations Ministry said. No one was hurt and there was no significant damage to the bridge, said ministry spokeswoman Irina Andriyanova.
Police presence was being beefed up Wednesday throughout the Stavropol region, said Stavropol police spokesman Igor Pogosov.
"A special emphasis is being put on the presence of plain-clothed officers, not only at bus terminals, but in all areas of mass accumulation of people, (such as) markets," Pogosov told Russia's NTV television.
During the raid on the bus, commandos set off concussion grenades, and a sniper shot the hijacker in the head when he peered out to investigate the noise, officials said.
Explosives experts later defused a bomb that was found attached to the body of the dead hijacker, said a spokesman for a Kremlin office in southern Russia, Alisher Khadzhayev.
Investigators questioned the 28 hostages remaining on the bus during the raid because of suspicions that the hijacker may have had accomplices among the passengers, Khadzhayev said.
All the passengers were cleared of suspicion and allowed to leave Tuesday night, he said.
The body of the hijacker, who was identified as Sultan-Said Idiyev, will be examined by forensic experts and then handed over to his relatives in Chechnya for burial.
After Idiyev seized the bus in Nevinnomyssk, he forced it along a major highway toward the airport in Mineralnye Vody. The bus was stopped just outside the airport, which was sealed off and ringed with troops, fire trucks and ambulances.
Twelve hostages were released throughout the day, including a 26-year-old man who had been shot and hospitalized.
The man, Viktor Zhukov, remained in a hospital Wednesday in Nevinnomyssk with a gunshot wound to a leg, said Col. Oleg Grekov, a spokesman for the Northern Caucasus branch of the Emergency Situations Ministry.
Two women from the bus were also in the hospital with heart problems, he said.
Violence from rebel Chechnya often spills over into the Stavropol region. Tuesday's hijacking echoed a 1994 incident in which hijacker with guns and grenade seized a passenger bus. Idiyev was demanding the release of five Chechens jailed in connection to that event.
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