The Thursday night blast was the sixth fatal bombing in Russia in less than three weeks, with nearly 300 people killed altogether. However, the St. Petersburg explosion was not on the same scale as the other apartment bombings, and authorities viewed it as unrelated.
President Boris Yeltsin's government is under increasing pressure to end the attacks and drive out Islamic militants from southern Russia, where they have been battling Russian forces for more than a month in Dagestan.
Russian leaders say the militants, many of them from the breakaway territory of Chechnya, are also responsible for the bombing campaign in Russia.
Police have been targeting dark-skinned people from southern Russia for document checks, and the two suspects detained in Moscow are both of Chechen origin. Police have detained a number of Chechens in recent days, but so far no one has been formally charged in any of the bombings.
Meanwhile, Prime Minister Vladimir Putin has given government agencies three days to come up with plans for strengthening security in transportation, communications, and energy installations, as well as in residential areas.
During a Cabinet meeting Thursday, he turned to the television cameras and appealed to citizens to protect themselves.
Â"I want to turn to military veterans, police veterans. Take the initiative on yourselves,Â" he said.
Moscow is abuzz with speculation the government will declare a state of emergency, which would allow Yeltsin to rule by decree. But Yeltsin has denied that and said he will serve out the remainder of his term, which expires in mid-2000.
Police discovered a Â"huge amountÂ" of explosive powder in a southern Moscow suburb on Thursday, hidden among sacks of sugar from a plant in southern Russia, security officials said. Police also uncovered six timing devices, apparently designed to detonate bombs, the Federal Security Service said.
|A rescue worker carries a cat saved from the|
building devastated in Volgodonsk Thursday.
At least 17 people were killed and 184 others were wounded, officials sai.
Volgodonsk, a city of 250,000 people, is close to the volatile Caucasus Mountains region, where the Russian forces have been fighting Islamic militants since early August.
Yeltsin's fitness to govern Russia has again come into question with the latest turmoil. Communist Party leader Gennady Zyuganov said Thursday's blast demonstrated Â"the paralysis of the entire law enforcement system in Russia.Â"
Â"An anti-terrorist operation plan ought to have been launched immediatelyÂ" after the first blast earlier this month, he said.
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