DREXEL HILL, Pa. (WPVI) -- The report of a gun led to a lockdown at an Upper Darby school and five students were taken into custody.The students, four males and one female, range in age from 15 to 17. All but one have been released to their parents.They all face criminal charges after police found a weapon, ammunition and drugs inside a student's locker and in a backpack.Students at Monsignor Bonner Archbishop Prendergast Catholic High School were dismissed at the normal time Wednesday afternoon but the school day had been anything but normal.Students tell Action News shortly after 11 a.m. they heard an announcement over the loud speakers."I was in third period and the principal said over the loudspeaker that there was a lockdown and we thought it was a drill but it turned out it wasn't," junior Gaetano Quintiliani said.Police say the school did everything right after a student reported that there was a gun on the property to a staff member."That student who reported it is a hero because when you have drugs and kids and guns it only leads to one thing - a tragedy," Upper Darby Police Superintendent Michael Chitwood said.Upper Darby police responded immediately and students say they spent two hours under the lockdown while officers searched the entire property including the rooftop."While we were sitting in the cafeteria, they were taking people one by one out to the main offices to talk to them," sophomore Jordan Williams said."We had to go against the wall and sit down and then we had to be silent until the police unlock us. We just saw that people were getting searched and that the lockers were getting searched," sophomore Catherine Horiel said.Police tell Action News they discovered a .9mm gun from a girl's locker.They found some marijuana and they recovered bullets in another backpack.The five students will be charged as juveniles."I was shocked. I thought it was crazy. I didn't think that would ever happen," Horiel said.The Archdiocese of Philadelphia issued a statement that said in part, "Incidents such as this demonstrate the importance of the school community working together to maintain a safe environment."The school will open as normal on Thursday.