Putin pledges tough line

President Vladimir Putin focused on the threat to Russia from Chechen rebels yesterday, vowing no deal with "terrorists", while his officials dodged questions about a lethal mystery gas used to end the Moscow theatre siege.

Of the 117 hostages who died in the theatre ordeal, all but two were killed by the gas pumped in at dawn on Saturday when Russian special forces ended the three-day siege by Chechen rebels, who had demanded Russian troops pull out of Chechnya.

Officials have refused to name the gas, even to the doctors trying to treat the critically ill, but London security expert Michael Yardley said it may have been BZ, a colourless incapacitant with hallucinogenic properties.

Sergei Mironov, chief doctor within the Kremlin administration, told reporters the death toll could still rise.

BZ acts on the peripheral autonomic and central nervous systems resulting in loss of motor coordination and memory, fainting, dry mouth, irregular heartbeats, nausea, vomiting, and hallucinations - all symptoms experienced by the hostages.

According to the US army, the side effects last 60 hours. Yesterday, an official day of mourning in Russia for the siege victims, Putin made no reference to the gas, preferring instead to pledge a hard line against the country's foes.

"Russia will make no deals with terrorists and will not give in to any blackmail," Russian news agencies quoted him as telling government ministers.

He was also quoted as saying Moscow would respond in "appropriate" fashion if there was any threat to use weapons of mass destruction against Russia.

Chechen leaders, who accuse Russian forces of brutality away from the world's gaze in their southern republic, offered again yesterday to sit down for talks - an offer the Russians have so far largely refused.

Denmark said it was moving a Russia-European Union summit scheduled for November 11 in Copenhagen to Brussels after Kremlin protests over a meeting by Chechen exiles in the Danish capital.

The theatre siege began when some 50 Chechen separatists seized a packed Moscow theatre during a musical.

It ended when troops stormed the building after using the mystery gas to stop "suicide squad" rebels detonating explosives strapped to their bodies.

Moscow's top doctor Andrei Seltsovsky said on Sunday hundreds of rescued hostages remained in hospital, including 45 in serious condition.

Frustrated and exhausted relatives, carrying food parcels and presents, gathered outside hospital gates in a desperate attempt to learn news of their loved ones.

Doctors at Hospital No. 13, where more than 300 hostages were taken, said most were expected to be allowed out yesterday.

Elated, the first to go home flashed smiles at the crowd. "When the gas came, I lost feeling in my body, I couldn't move my fingers. I lay down on a red fur coat and after that I can't remember," said Andrei Naumov, 17. "When I awoke, I felt I was alive."

Flags flew at half mast and light entertainment was cancelled in the city of more than 10 million. Schoolchildren stood for a minute of silence before starting classes. Wednesday's Champions' League match in Moscow between Spartak Moscow and FC Basel was cancelled as a mark of respect.

Passers-by placed fresh flowers and candles outside the theatre where the hostages were held. Fifty hostage-takers, nearly all of them, were killed in Saturday's assault.

"My heart is broken," an elderly local resident said, wiping tears from her cheeks. "I couldn't move from my balcony all night. I just stood there, helpless."

Putin apologised within hours of the dawn raid on Saturday for proving unable to save all hostages.

Initial relief that accompanied the first reports that perhaps only 10 hostages had died was replaced by doubts about the mysterious gas as the death toll mounted over the weekend.

"They poisoned us like cockroaches," a woman quoted her daughter as saying in Kommersant daily, in a front-page spread under the headline "Overdose".

One doctor expressed frustration at the lack of information. "I saw no gunshot wounds at all. Those who died had swallowed their vomit or their tongue or their hearts had stopped," he told the Nezavisimaya Gazeta daily.

"If only we had known beforehand! If they had told us that we would be getting large numbers who had lost consciousness or heart failure, it might have been a bit different."

A spokesman said the US embassy had asked Russia for details of the gas so one of their nationals still in hospital suffering from its effects could be better treated.

Despite the controversy, British Prime Minster Tony Blair backed the decision to intervene.

"There are no easy, no risk-free, no safe solutions to such a situation," he told parliament yesterday.

"And I hope people will understand the enormity of the dilemma facing President Putin as he weighed what to do, in both trying to end the siege with minimum loss of life and recognising the dangers of doing anything that conceded to this latest outrage of terrorism from Chechnya."

Chechnya's elected but now fugitive president Aslan Maskhadov said through an aide that he was ready to hold unconditional talks with the Russians to find a political solution to the bloody, protracted conflict.

"We can only solve it politically," his envoy Akhmed Zakayev told a Chechen gathering in Copenhagen.

"President Maskhadov, as before, is ready without any preconditions to sit at the negotiating table. It is up to the Russian leadership."