Rescuers from nearby coal-mining towns of Shakhty and provincial capital Rostov-on-Don have been rushed to dig out the survivors from under the rubble, Shoigu said on NTV channel.

The authorities see Thursday's blast as a part of the chain of terrorist bombings on apartment blocks in Buinaksk (Dagestan) on September 3 and in Moscow on September 9 and September 13 in which over 260 people were killed, FSB (the former KGB) spokesman Alexander Zdanovich was quoted as saying by radio Ekho Moskvy.

Reacting to Thursday's blast, President Boris Yeltsin said in his televised remarks, ``We have enough forces and potentiality to crush terrorism in Russia.''

Talking to reporters before his meeting with Prime Minister Putin, Yeltsin said Thursday's blast and anti-terroristaction would be focus of their talks.

Earlier, on Wednesday, an obscure terrorist group -- Dagestani Liberation Army (DLA) -- had claimed responsibility for earlier blasts and in a statement vowed to ``avenge each and every death of Chechen and Dagestani children and women killed under the Russian bombs''.

No transport links with Chechnya : Yeltsin

MOSCOW: President Boris Yeltsin was quoted as saying on Thursday that Russia was working on tightening its border with the breakaway region of Chechnya and that transport links with it should be cut.

Interfax news agency quoted Yeltsin as saying at a meeting with foreign minister Igor Ivanov there should be ``no transport links'' with Chechnya, blamed by Moscow for helping Muslim radicals carry out a series of bombings in Russia that have killed more than 260 people. Chechnya denies involvement.

``We have a lot of work to do on this and we will do it,'' Interfax quoted Yeltsin as saying. He spoke after Russians awoke to news of the thirdbomb attack on a residential building in a week, this time in the southern Russian town of Volgodonsk.

-- REUTERS