Security forces said at least four of the hostage-takers were thought to be still at large as of early Saturday morning, Russian news agency Itar-Tass said. Sporadic gunfire could still be heard throughout Beslan.
The agency report came as Russian security forces said they had captured three hostage-takers. The hostage-takers, whose identities have yet to be confirmed, had been holed out in the basement of the school rocked by several explosions and a three-hour firefight earlier in the day.
Russian security forces said they were forced to storm the school when fleeing children were shot at.
As many as 250 people - mainly children - were killed in the ensuing carnage, Interfax news agency said, while 704 people, 259 of them children, have been hospitalised with injuries resulting from the violence, Tass reported.
On Saturday morning, there was still some confusion as to the exact number of hostage-takers, how many had been killed or apprehended, or if any had escaped to neighbouring Ingushetia.
The situation has remained tense
amid sporadic gunfire
A commander of Russian forces at the scene said most were killed "and I doubt any managed to flee". There were thought to be about 40 hostage-takers in all.
Russian security forces killed 20 hostage-takers involved in the siege, 10 of whom were Arabs, Interfax said.
However, Russian officials were unable to provide an explanation as to how the bodies of the hostage-takers were identified.
News agencies later spoke of eight armed persons killed, three arrested and four still at large.
Chechen resistance spokesman Ahmad Zakayev said the armed group which took hundreds of people hostage at the Beslan school in southern Russia was not Chechen.
"The hostage takers were Ingush, Ossetians, Russians, but not Chechens," said Zakayev, once a spokesman for Chechnya's separatist president Aslan Maskhadov.
"But of course, their demands have all to do with Chechnya, so whatever has happened, the Chechens will be held responsible. That's what I'm afraid of," he said on Britain's Channel 4 television.
It was not clear what had triggered the dramatic battle, a few hours after Russia insisted it would not resort to force to free the children, parents and teachers being held for a third day without food or water.
Russian forces stormed the school
when fleeing children were shot at
Children who were able to flee the melee told Russian television that they believed a bomb strapped to the ceiling of the school building came unhinged and was set off on its own.
This set off a chain reaction prompting the escape of dozens of students, teachers and parents and leading to the storming of the school by Russian special forces.
However, their account could not be corroborated and Russian officials are still investigating what set off the explosions which rocked the school.
Earlier, several blasts shook the area as armed fighters fired grenades sporadically from the school.
A North Ossetian regional official, Lev Dzugayev, said the fighters appeared to be firing because they thought they detected security forces moving outside.