Vladimir Putin’s daring bid to host the Winter Olympics in the politically dicey Caucasus Mountains was his way of showing the world that he had created a stylish, fun-loving country, a Russia that had defeated violent separatism once and for all.

It was a gutsy gamble — and the remaining separatists vowed to do whatever they could to disrupt the pageant. The potential costs of failure were driven home Monday when an apparent suicide bomber shredded a crowded trolley bus in the city of Volgograd. That came on the heels of a bomb attack Sunday on the city’s railroad station. The two explosions killed 34 people and injured dozens.

Security at the site of the Olympics is watertight, so Islamist extremists have vowed to bring violence to the Russian heartland. Volgograd, about 400 miles from Sochi and a city storied in Russian history, offers itself as a tempting target.

Putin demanded a heightening of security Monday amid fears that foreign guests in particular could be frightened away from the Winter Games. The two bomb blasts effectively blunt his recent charm offensive, seemingly aimed at the West with the Olympics in mind, that saw the release of oil tycoon Mikhail Khodorkovsky, two members of the band Pussy Riot, and the crew of the Greenpeace ship Arctic Sunrise, held on criminal charges since late summer.

Although no groups asserted responsibility for the Volgograd attacks, officials said they think they were related — and linked to an extremist group in Dagestan.

Russia has been engaged in an enduring and violent struggle with extremists since it defeated a separatist movement in Chechnya in the 1990s. After the war, a growing number of separatists turned radical, evolving into Islamist extremists who have launched sporadic terrorist attacks on the country, from Moscow to the hinterlands. They have also carried out a low-grade battle with authorities that is now centered in the southern region of Dagestan, inflicting more casualties among Russian interior forces than the U.S. military suffers in Afghanistan.

Putin has staked his prestige on hosting a successful Winter Games in Sochi and demonstrating in the process the safety of the resorts at the western end of the Caucasus Mountains.

The security agencies have been clamping down hard in Sochi, watching and calling in for questioning those who express unwelcome opinions, including environmental and human rights activists. Russia is spending $2 billion on security there.

As the Vedomosti newspaper put it in a recent editorial: “The authorities want to clear the area around Sochi from any disgruntled elements that could compromise a positive image of the country as the host of the Olympic Games. Nobody seems to care that the current unwillingness to maintain a dialogue with society may adversely affect the course of events after the Olympics.”

The president of the International Olympic Committee, Thomas Bach, said he is confident that Russian authorities will deliver a “safe and secure” Olympics in Sochi, the Associated Press reported.

The heavy protection for Sochi appears to have drawn resources away from other parts of this huge country. On Monday, Putin met with the head of Russia’s Federal Security Service and directed him to plan for heightened security nationwide.

[See: The path of the Olympic torch]

(The Washington Post)

The National Anti-Terrorist Committee announced Monday that more than 4,000 security personnel will be involved in a huge sweep in Volgograd. Volunteers were also being organized to patrol the sprawling city along the Volga River, where Soviet and Nazi forces met in an epic World War II battle in 1942 and 1943, when the city was known as Stalingrad. That history gives Volgograd a resonance in Russians’ imagination, even though the country has become somewhat inured to terrorist attacks.

On Friday, three people were killed in an explosion in Pyati­gorsk, south of Volgograd and east of Sochi in the foothills of the Caucasus. A bomb had been hidden in a car parked on a busy road near the offices of the traffic police.

The chance that terrorist activity will spoil the Olympics has been a prime worry for security officials — especially given the publicity generated by April’s Boston Marathon bombing, carried out by two young men who were thought to be sympathetic to the Chechen separatist movement.

Doku Umarov, a Chechen rebel leader who authorities think is operating out of Dagestan and leading a movement to establish an Islamic emirate in southern Russia, called in July for resuming a campaign of terrorist attacks against civilian targets in Russia. He denounced the Sochi games as a defilement of the ­sacred ground of the area’s original inhabitants, the Circassians.

Umarov has asserted responsibility for several terrorist attacks, including a bombing at Moscow’s Domodedovo airport in January 2011 that killed 37 people. The United States has offered a reward of up to $5 million for information about Umarov, U.S. Ambassador Michael McFaul said Monday on Twitter.

In a statement of condolence released by the White House, the spokeswoman for the National Security Council, Caitlin Hayden, said: “The United States stands in solidarity with the Russian people against terrorism. The U.S. government has offered our full support to the Russian government in security preparations for the Sochi Olympic Games, and we would welcome the opportunity for closer cooperation for the safety of the athletes, spectators, and other participants.”

The U.S. Olympic Committee also offered condolences to those affected by the bombings.

“We are always concerned with the safety of our delegation and the Sochi Games are no different in that regard,” committee spokesman Patrick Sandusky said in a statement. “We will continue to work closely with the local organizing committee, our State Department and law enforcement agencies to ensure that all appropriate measures are in place.”

Sunday’s bombing took place, according to officials, when a railroad inspector at a station entrance tried to stop a man who looked suspicious. The man detonated his explosives, killing 18 people, including the inspector. The Interfax news agency quoted an anonymous law enforcement official as saying that police think the bomber was a native of the Mari El region of Russia, farther north along the Volga, and that he was a paramedic who had converted to radical Islam.

The bomber was tentatively identified as Pavel Pechyonkin, who worked for five years at an ambulance service in the predominantly Muslim city of Kazan.

A video made by his parents this year and posted on YouTube shows them pleading with him to return from Dagestan and renounce violence.

“Do all Muslims go around with weapons?” his father, Nikolai, said in the video. “You are the only one so stubborn. What harm have people done you? . . . You are going to kill children.”

In a reply video, Pechyonkin said, “I have come here only to make Allah pleased with me, to earn heaven.”

The attack on the trolley bus Monday also appears to have been the work of a suicide bomber, officials said. The roof was blown off the bus, shattering windows in a building nearby. Investigators calculated that the bomber, whom they said was a male, was carrying about nine pounds of explosives. Fourteen people were confirmed dead.

“The city is full of fear,” Yana Deyeva, a Volgograd resident, wrote in a blog, adding that rumors are constantly spreading about possible attacks throughout the city. Many residents appeared reluctant to use public transportation.

Volgograd declared a period of mourning through Friday. The city was also the site of a suicide bombing on a bus in October that left six people dead.