This blast has however raised questions among Russian authorities who did not exclude the possibility of a bombing attack. The three victims that died at the complex in the city of Biisk were all females and all three worked in the shopping complex. A criminal case was opened on suspicion of negligence.
The federal Investigative Committee had the following to say: "According to preliminary information, a household gas explosion may have been the cause." There was no mention of foul play or of any militant attack in the early morning explosion that took the three lives more than 1500 miles east of Sochi. Among the last confirmed terrorist attacks he one from the southern city of Volgograd that took place in the last days of December stands out. Back than 34 people were killed in a suicide bombing attack. Authorities are on a lookout for such attacks ever since, especially with the Olympic Games going on.