The death toll from the school siege in Beslan rose to 333 Sunday following the overnight deaths of three more children, medical authorities in the town confirmed. Up to 420 people, including 234 children, are being treated in Beslan's hospital and clinics throughout North Ossetia for injuries sustained in the attack. About 55 of those are reported to be in a critical condition, medical authorities said. Authorities have said that about half the deaths were children, and about 260 people remain missing. Recovery teams, however, spoke of 500 dead. The first funerals were being held Sunday. Meanwhile North Ossetian Interior Minister Kazbek Dzantiyev has resigned, saying that after everything that happened, he could no longer remain at his post, reported Interfax news agency. About 700 people were injured during the crisis, which began Wednesday when suspected Chechen and Arab militants seized the school on the first day of the new term, a festival-like day attended by a large number of parents. The standoff ended Friday with security forces storming the school as explosive devices packed with bolts and nails were detonated among the estimated 1,200 hostages packed into the school's sports hall, authorities said. The explosions caused the roof to collapse, charring many of the victims. Most of the hostages killed Friday died as a result of the terrorists' bombs and falling debris, police in North Ossetia said. Authorities said all 26 militants were killed when security forces stormed into the school, adding that 10 of them were Arabs.