Earlier, police fought pitched battles with opposition supporters who had held daily protests since a Feb 19 poll that the opposition said was rigged in favour of Prime Minister Serzh Sarksyan to become president. At least one person was killed.

About 2,000 protesters remained after those clashes in a square in the centre of Yerevan armed with metal rods and Molotov cocktails as army trucks headed towards the capital.

But the crowd melted away after a message was read out from Levon Ter-Petrosyan, the protest leader and defeated challenger in the election, urging his supporters to go home.

'I do not want any victims and clashes between police and innocent people. That is why I am asking you to leave,' said the message from Ter-Petrosyan, a former president who since Saturday has been barred by police from leaving his home.

He said in his message he would be holding negotiations with the government, reversing a previous stance that talks were out of the question unless the election result was overturned.

A hard-core of about 60 protesters initially refused to go home and set fire to police jeeps abandoned after the earlier clashes. But a few minutes later all the protesters had gone, leaving the square strewn with debris.

Armenia is a former Soviet republic of 3.2 million people in a Caucasus mountains region that is emerging as a key transit route for oil and gas supplies from the Caspian Sea.

The violence was the worst since 1998, when a mass uprising had forced Ter-Petrosyan to resign.

Fault line
Mr Sarksyan's opponents accused him of stealing victory through ballot-rigging and intimidation. Mr Sarksyan denied this and Western observers said the vote had been broadly fair.

The main political fault-line is that Ter-Petrosyan's supporters accuse outgoing President Robert Kocharyan of running a crony state where only those with ties to the ruling elite have access to business opportunities and decent jobs.

The Organisation for Security and Cooperation in Europe issued a statement saying it 'condemned the use of force against peaceful demonstrators'.

When the violence erupted on Saturday, demonstrators armed with metal rods and sticks pelted police with Molotov cocktails, setting cars ablaze. At one point police fired their weapons into the air, sending tracer fire through the night sky.

Television pictures showed a body being driven from the scene on the roof of a car, with protesters hanging on to the sides of the vehicle to hold it in place. Shops in the centre of the city were looted.

Mr Kocharyan said some demonstrators had fire arms and grenades and were planning to launch a coup d'etat. The opposition rejected this, saying police had attacked a peaceful protest.

'If participants in the disorder fire at police, I have no choice but to resort to the army's help,' Mr Kocharyan said in remarks broadcast on television. 'And I am obliged to safeguard the safety of our citizens.'

The state of emergency, effective until March 20, bans all protests and imposes censorship on the media. Kocharyan said he was introducing the restrictions 'to prevent a threat to constitutional order'. -- REUTERS