Moscow, 17 September 1999 (RFE/RL) - Interior Minister Vladimir Rushailo said today an overnight blast in St.Petersburg that killed two people was apparently not linked to a recent spate of bombings in Russia. Rushailo said the blast, which shook an eight-storey building in Russia's second-largest city shortly before midnight, was more likely aimed at the residents of one of the apartments in the building. Initial reports after the blast had suggested it could have been a gas leak but later police were quoted as saying it was caused by a bomb. The St. Petersburg blast was the sixth explosion in Russia in less than three weeks. Nearly 300 people were killed in the previous blasts. There has been no credible claim of responsibility but Russian officials have blamed the blasts on Islamic separatists in the North Caucasus. Russian media reported that two men of Chechen origin were detained today on suspicion of involvement in two previous bomb attacks in Moscow. Russia's upper house -- the Federation Council -- is meeting today behind closed doors to discuss the security situation in the country following the bomb attacks.