As the Sochi Olympics open, the Russian government says it's doing everything possible to ensure safety at the Games — even as the U.S. warns airlines that enemies may try to smuggle toothpaste tubes carrying explosives into Russia.

"We can guarantee the safety of the people as well as any other government hosting a mass event [can]," said Russian Deputy Prime Minister Dmitry Kozak on Thursday, one day before the opening ceremony.

While the Winter Games officially open Friday, some qualifying events are already underway.

Security concerns have been at the forefront of the Sochi Games for months. They were renewed this week when the U.S. Homeland Security Department warned airlines flying to Russia that toothpaste may be the weapon of choice for people targeting the Games this year.

Kozak said Russia is taking steps to collaborate with nations to build a database on potential terrorists.

"There is no reason to believe Sochi, in Russia, is under more threat than any other city in the world," he said.

Kozak says the fear of terrorism is always present at big sporting events, in Russia or anywhere else. But he also believes "the level of fear should be lower" surrounding the Sochi Games.

The Russians aren't sharing as much information with other countries as the Chinese did when they hosted the Beijing Summer Olympic Games in 2008, CBS reported Thursday, quoting U.S. officials. At the same time, however, U.S. intelligence agencies know of no specific plot or threat.

Physical advantages

Despite Sochi's location in the volatile north Caucasus region, it has several physical advantages.

For example, there is currently only one road that connects it to the rest of Russia, CBC's Nahlah Ayed reports from the Olympic site. A road to the south has been shut down for the duration of the Olympics.

"There's only a few other ways into Sochi," she said. "One is the airport, which is obviously being very closely monitored, and a single railway line. There's the [Black Sea] coast, but there are more ships patrolling there.

"And in the mountains, there are tens of thousands of special forces soldiers who are keeping watch."

As well, she said, the condensed design of the site — the most compact ever for a modern Olympic games — makes patrolling the site and keeping it secure much easier.

Meanwhile, the chief organizer of the Sochi Olympics says a record number of world leaders are coming to the Games.

Record list of leaders

Dmitry Chernyshenko said 65 heads of state and government and international organizations are expected to attend Russia's first Winter Olympics.

He says it's a record for Winter Games and three times the number of leaders who attended the 2010 Olympics in Vancouver.

However, Sochi organizers have declined to provide the names of the leaders coming to the opening ceremony or the countries they represent.

A number of top world leaders won't be at the Olympics, including:

Canadian Prime Minister Stephen Harper.

U.S. President Barack Obama.

French President Francois Hollande.

British Prime Minister David Cameron.

As well, neither German Chancellor Angela Merkel nor German President Joachim Gauck, who serves a largely ceremonial role in the German government's structure, is expected to attend the Sochi Olympics.

The Games come amid Western criticism of Russia's record on human rights and its law banning gay "propaganda" among minors.