PARIS (AP) — The European Court of Human Rights says that Russia failed to adequately protect victims of a 2004 school siege in the city of Beslan that left more than 300 people dead.

More than half the hostages killed were children.

In a ruling Thursday, the France-based court said authorities did not take necessary preventive measures to save lives. It said the security forces' use of tank cannon, grenade launchers and flame-throwers contributed to casualties among the hostages. It noted failures to increase security before the attack despite imminent threats against schools in the area.

Armed radical Islamic assailants seized the school on the first day of class, prompting a long standoff that ended in explosions and gunfire.