"I expected the death penalty, and it is not right he was sentenced to life in prison," Rita Sidakova, a leader of the group Mothers of Beslan, said in an Associated Press report. "He is guilty of the deaths of hundreds of people but himself has remained alive and my daughter is dead."
In handing down the sentence, Judge Tamurlan Aguzarov told the court a government ban on the death penalty, imposed when Russia joined the Council of Europe in 1996, led to his decision.
"(Nurpashi Kulayev) deserves the death sentence but because the Russian government has introduced a moratorium on carrying out death sentences, I sentence him to life imprisonment."
Kulayev is accused of participating in the deaths of 331 people, more than half of them children, held hostage during the takeover of a Beslan school on the morning of Sept. 1, 2004. The victims died after two days when two unexplained explosions collapsed the roof of the school and when police engaged in a shoot-out with the militants.
Thirty-one of Kulayev's associates, who launched the siege in an effort to force Russian troops from the embattled Chechen province, are believed to have been killed in the shootout, Reuters reported. Eleven Russian soldiers also died.
Kulayev maintained his innocence throughout the trial.
Families of the victims and survivors blame many of the deaths on Russian troops, who they say initiated the roof's collapse when they fired at the school from tanks setting it on fire, the AP reported.
"He received the punishment he deserved," Taimuraz Chedzhemov, a lawyer for the victims' group Voice of Beslan, told Reuters. "But the sentence ... has not answered all the questions around the terrorist act -- the reasons for the capture of the school, the killing of so many people or ... who is to blame for the tragedy that happened."
A member of the Chedzhemov's group, who lost her daughter in the siege, welcomed the verdict saying Kulayev could serve as a witness in any further investigations.
"Preserving Kulayev's life gives us hope that all circumstances of the terrorist act in Beslan sooner or later will be investigated," she told the AP. "Alive, Kulayev can give evidence on the main part of the case. We hope to learn the truth about Beslan."