The assault brought howls of protest from liberals in Moscow, scattered resistance on the ground and a plea for peace talks from President Boris Yeltsin, who vanished into a hospital on the eve of what could prove the most perilous moment of his presidency. As Russian forces streamed towards the capital of Grozny in three separate columns, supported by attack helicopters and Su-25 fighters, the Chechen leader, Dzhokar Dudayev, said the attack would lay "a bloody blanket" across the north Caucasus, home to more than 30 mostly Muslim ethnic groups.
A government spokesman in Moscow said the troops would pause before entering Grozny, a city of 400,000 founded in the last century as a Cossack fortress. The name means Terrible or Fearsome. This seemed to suggest a strategy of siege aimed at forcing Mr Dudayev's capitulation without the large loss of life that a head-on assault would risk.
Interfax news agency reported that a priority task for Russian troops was an oil refinery outside Grozny and a strategic oil pipeline that passes through the region. In a clear attempt to woo the local population Russia's military muscle was accompanied by vast quantities of food.
President Yeltsin did not appear in public but Itar Tass news agency carried what it says was an address to the nation. "We should avert a breakdown in talks," Mr Yeltsin was quoted as saying. "Our aim is to find a political solution to the problems of one of the members of the Russian federation and to protect its citizens from armed extremism."
Russian liberals, including some of Mr Yeltsin's closest former allies such as the former prime minister, Yegor Gaidar, have denounced military action as a threat not only to lives in Chechnya but to Russia's fledgling democracy. A statement from Mr Gaidar's Russia's Choice party warned of a hardline ascendancy in the Kremlin that "dreams of murdering Russia's democracy and forcing the people back behind barbed wire."
But only 500 people turned out for a demonstration in Pushkin Square in central Moscow to protest against the military intervention.
Aside from Mr Yeltsin's brief appeal there was only ominous silence from the Kremlin yesterday. Mr Yeltsin, who serves as the country's commander in chief, is said by his office to have had nose surgery to relieve breathing trouble.
A statement on Saturday did not say when the operation took place but only that recovery would take about eight days during which Mr Yeltsin could still work.
President Yeltsin has not been seen in public since his return from the OSCE conference in Budapest last week. On Friday, only two days after his Defence Minister, Pavel Grachev, met Mr Dudayev and vowed not to use force, Mr Yeltsin issued a decree ordering "the use of all means at the disposal of the state" to tame Chechnya's three-year-long secessionist rebellion.
Mr Yeltsin tried to impose a state of emergency on Chechnya when it first broke with Moscow in 1991, but he backed down after parliament refused to ratify the move.
The main flash-point in the early hours of yesterday's invasion, launched shortly before dawn, came near the town of Karbulak, a small settlement in the region of Ingushetia, which borders Chechnya and is inhabited by ethnic kin of the Chechens.
The region's president, Ruslan Aushev, was quoted as saying his people were blocking Russian troops in Ingushetia. Several people were reported killed. Concerted resistance, however, seems to have been minimal.
The Chechen government, which declared unilateral independence from Russian at the end of 1991, appears divided itself over how to respond.
The Foreign Minister, a Jordanian-born businessman called Yusef Shamsudin, said Chechnya would now boycott talks scheduled for later today in the nearby Russia-controlled town of Vladikavkaz.
"We are talking with guns now," he said.
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