Suspected Chechen rebel suicide bombers drove vehicles packed with a tonnes of explosives into the local government headquarters in Grozny this morning, gutting the building and killing at least 41 people.
Two huge explosions went off within a minute of each other, devastating a four-storey government building, rows of official vehicles and spewing debris over a wide area.
In October, Chechen rebels seized some 800 hostages in a Moscow theatre. Forty-one rebels and 129 hostages were killed when Russian special forces stormed the theatre.
The rebels are fighting for independence for the mostly Moslem southern province of Chechnya and want Russian troops there to withdraw.
Television pictures in Grozny showed bodies scattered on the frozen ground as small groups of dazed staff and security personnel, blood pouring from head wounds, staggered towards medical crews.
Chechnya's acting prosecutor Mr Vladimir Kravchenko said said the death toll had risen from 32 to "about 40", while Kremlin officials said around 80 were injured.
"The power of the explosion was about one tonne, the explosion crater is about six metres," Mr Kravchenko said by telephone from Grozny.
There were no immediate claims of responsibility for the bombing but officials blamed it on elected Chechen President Mr Aslan Maskhadov, ousted when Russian troops returned to Chechnya in October 1999 after a three-year break.
The Grozny attack appeared aimed at shattering Russian claims that life in Chechnya is returning to normal. President Vladimir Putin plans a March referendum on a political settlement that would keep Chechnya within Russia.