The sole surviving member or the gang that attacked School No 1 in the southern Russian town of Beslan was sentenced to life in prison today after being found guilty of murder and terrorism.

Prosecutors had asked the court in Vladikavkaz, the capital of the republic of North Ossetia, to ignore a ten-year moratorium on capital punishment and pass a death sentence on Nur-Pashi Kulayev.

But after a year-long trial, the judge, Tamerlan Aguzarov, said that he had no choice but to hand Kulayev a life term as he finished reading a verdict that has taken eight days to deliver.

"Kulayev deserves the death penalty, but is sentenced to life in prison because a moratorium is in place," he said.

At least 331 people died in the September 2004 raid, more than half of them children. But although Kulayev, 25, admitted that he took part in the siege, he denied personally killing anyone and had pleaded not guilty.

The vast majority of the victims were killed in a hail of explosions and gunfire after the detonation of one of the bombs that a group of Islamic militants had strung around the gymnasium where they held more than 1,100 hostages for three terrifying days.

As the judge read the verdict, some victims’ mothers threw themselves shrieking on the glass-and-metal cage where Kulayev has stood throughout the year long trial. Police struggled to restrain them.

Some of the mothers held banners reading, "There is no forgiveness of the authorities who let Beslan happen," as well as photos of tanks and dead children.

Many survivors and their relatives accuse authorities of botching the rescue operation and said victims had died as a result of the troops’ firing. Mr Aguzarov said that 16 hostages whom the militants executed on the first day of the assault had died in part due to Kulayev’s actions.

Although the guilty verdict brings Kulayev’s trial to an end, the main federal investigation into the Beslan massacre is still continuing and is not expected to wrap up until later this year.

Many questions remain unanswered about the school siege, how it was seized and how the authorities reacted. Families of those killed in the massacre have demanded that top federal government officials also be held to account for their actions during the crisis.

The siege started on September 1, 2004, when a large group of gunmen reportedly demanding the withdrawal of Russian troops from Chechnya seized more than 1,000 children, parents and teachers and held them hostage inside the school.

Kulayev admitted being amongst them but denied firing any shots or being directly responsible for any deaths, claiming that had joined the gunmen only at the behest of his elder brother who was among the hostage-takers killed by security forces. He also said that he did not know where they were going or what their plan was.

Shamil Basayev, a Chechen rebel warlord, claimed responsibility for the Beslan school attack, which ended three days after it began in a horrific bloodbath marked by ferocious and chaotic fighting between security forces and the hostage-takers

The battle ended in the deaths of 331 people, including 186 young children. Of the hostage-takers, 31 were killed and Kulayev was, according to Russian authorities, the only one to be captured alive.

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