Winter Olympics countdown tinged with fear after Volgograd blasts All over Russia, clocks in public places show there are only 38 days to go until the start of the Winter Olympic Games in Sochi. But the countdown, intended as a display of pride and anticipation, has become fraught with fear after a string of terrorist attacks in the region neighbouring the venue. Terrorism experts say the two deadly bomb blasts in Volgograd within 24 hours have succeeded in shattering Russia's confidence that a massive security operation can guarantee a safe games. "The very, very tight security in and around Sochi has created a very difficult operating environment for anyone aiming to target the Olympic venues themselves, but the Volgograd attacks illustrate that it is impossible to protect softer targets in the region around them," says Matthew Clements, an analyst at IHS Country Risk in London. Thirty-one died and 89 were injured in two suicide bombings in the main train station and on a trolleybus in Volgograd on Sunday and Monday. The death toll is expected to rise as some of those in hospital are in critical condition. Russia's Federal Investigative Committee said on Monday the two blasts appeared to be connected and that the bombs may have been prepared in the same place. This is widely seen as an indirect admission that the security forces, despite their focus on threats to the Sochi games from a long-running insurgency in the North Caucasus, cannot guarantee safety for everyone planning to attend. The twin explosions were the deadliest attacks in Russia since a suicide bombing at Moscow's Domodedovo International Airport in January 2011. They came soon after a blast in Pyatigorsk, another town in the same region, that killed three last Friday, and follow a suicide attack on a Volgograd bus last October. Government officials keep repeating that they assess the overall level of risk for Sochi as no higher than London faced when it hosted the Olympics in 2012. "That may be true, but there is a difference between being a general threat target and holding an event like this on the doorstep of a region with a domestic insurgency of the kind we see in the North Caucasus," says Mr Clements. Alexander Zhukov, president of the Russian Olympic Committee, responded to the latest attack by saying no additional security measures would be taken in Sochi. "Everything necessary has been done," he said on Monday. The International Olympic Committee has also weighed in. "I am certain that everything will be done to ensure the security of the athletes and all the participants of the Olympic Games," said Thomas Bach, IOC president, in a statement . Indeed, Moscow has devoted unprecedented resources to secure Sochi. Through a new law, the government created a security zone 100km long and 40km wide, which only visitors with games-related documents will be able to enter. Being deployed there are 25,000 police officers and 8,000 personnel from other security agencies, backed by up to 30,000 military personnel, creating a total security staff of more than double that for the London Olympics. The London games, where more athletes and visitors needed to be protected, used 12,000 police and 18,000 troops, according to Jane's, the security consultancy. But experts warn that this effort, while making Sochi a tougher target, is also displacing the threat. "When resources are finite (and they are), then that effort must be at the expense of somewhere else," writes Mark Galeotti, an expert on transnational crime and modern Russia at New York University, in a blog post. While we can't rule out attacks in the major cities of European Russia, so far we are seeing the shift of the target area north and west, into the rest of the Southern Federal District. Everything necessary has been done Alexander Zhukov, Russian Olympic Committee president While Volgograd is most vulnerable as the region's main transport hub, analysts have also issued warnings of heightened risk for Krasnodar and Stavropol. No group has claimed responsibility for either of the Volgograd attacks, but security officials assume suicide bombers from the North Caucasus are to blame. Terror experts believe that while the insurgent groups from the region lack a joint command and strict organisational structure, they are mobile and motivated enough to continue hitting traffic infrastructure in the Russian heartland. Mr Clements says an attack on an airport would represent the maximum possible escalation from the latest bombings, although he argues that the North Caucasus groups are unlikely to be able to penetrate security measures at and around airports ahead of the Sochi games. But the railways, the main means of transport for most Russian visitors to the Winter Olympics, remain vulnerable. This is highlighted by the results from the investigation into the October bus bombing in Volgograd. According to police reports, the attackers had visited some shopping malls but settled for the bus as a target only at short notice. One Russian security expert says: "The main goal was to hit the highest concentration of people possible."