Mindre enn 24 timer etter terroraksjonen mot jernbanestasjonen i Volgograd, er minst ti mennesker er blitt drept av en ny terrorbombe i samme by, denne gangen på en buss full av mennesker.
Ingen har påtatt seg ansvaret for bomben, men igjen mistenker en at det står en selvmordsbomber bak.
Security has been tightened at railway stations and airports across Russia.
A spokesman for Russia’s Investigative Committee said both explosions were now being treated as acts of terrorism.
The latest explosion took place near a busy market in the city’s Dzerzhinsky district.
The explosion removed much of the bus’s exterior and broke windows in nearby buildings.
Observatører begynner å mistenke at bombene i Volgograd, nå den tredje i rekken, er en avledningsmanøver i påvente av et større angrep et annet sted, og dette annet sted er høyst sannsynlig Sotsji der OL begynner 7. februar.
Sikkerhetseksperten Andrej Soldatov sa etter søndagens bombe på jernbanestasjonen i Volgograd:
“It is the second attack on Volgograd with no apparent reason, and it now looks like part of something bigger,” said Andrei Soldatov, a security expert who runs the agentura.ru website. “It looks like a diversion – a very effective tactic to get the FSB thinking about how to protect Volgograd and the transport system before you attack somewhere else.”
Similar diversionary assaults preceded some of the most notorious terrorist attacks in the mid-2000s, including the suicide bombing of two airliners one week before the 2004 Beslan school siege.
Some have speculated that targeting Volgograd – a Russian heartland city conveniently within striking distance of the Caucasus – is a sign that terrorists are wary of the heightened security around Sochi, But Mr Soldatov said an attack on the Games was still possible.
“I think it is best to be pessimistic in the current situation,” he said.