BARTOW, Fla. -- Authorities in central Florida say two middle school girls brought knives to school in a foiled plot to kill classmates, cut them up and drink their blood.Arrest affidavits released Wednesday by the Bartow Police Department say the two girls, ages 11 and 12, were armed with knives Tuesday at Bartow Middle School before they were caught. No one was hurt.Investigators say the girls said they wanted to kill at least 15 people and were waiting in the bathroom for smaller students so they could overpower their victims.The affidavit says the students planned to cut their victims' throats, cut up their bodies, eat the flesh and drink their victims' blood.The students also told police they are Satan worshippers.Authorities say the students then planned to kill themselves."We will leave body parts at the entrance and then kill ourselves," one of the girls said, according to police.Police say the plot was foiled when administrators searched for them after they didn't show up for class.The students were charged with conspiracy to commit murder, possession of a weapon on school property and disruption of the school functions.They will not be allowed to return to school.Police said the students did not have any known prior behavioral issues and authorities believe the parents did not have any knowledge of the planned attack.