Large police presences converged on multiple schools across Pennsylvania Wednesday as authorities investigated active shooter hoaxes.Police responded to Central Catholic and Oakland Catholic high schools in Oakland, around 10:18 a.m.There were no reports of injuries. No active shooter was found at any location. Additionally, the University of Pittsburgh and Carnegie Mellon lifted lockdowns.School administrators say the call of an active shooter did not come from inside the school. They were alerted by an outside source which activated their blue alert active shooter drill. Law enforcement arrived to find students and faculty in lockdown.They checked every room, every available space, to make sure there was no one inside the building, other than who should have been there, students and faculty," said acting Police Chief Thomas Stangrecki. "There was no active shooter. They checked every room.""Out of an abundance of caution, all PPS schools, offices, and facilities are on a modified lockdown for the rest of the day," Pittsburgh Public Schools said in a statement. "Modified lockdown means only existing appointments or meetings will be honored."State police say the threats appear to be computer-generated “swatting calls,” but they were all being taken seriously. State police out of the Blair and Bedford county areas tweeted, “PSP Hollidaysburg and Rockview stations are responding to active shooter threats at local schools that have been called in by telephone. We are treating each incident with standard law enforcement protocols. However, the calls are believed to be computer generated swatting calls.”"We are investigating a series of phone calls made to 9-1-1 centers involving threats of an active shooter situation or bomb threat at PA schools," state police tweeted. "At this time, all claims in these calls have been determined to be false. The investigation is ongoing."An Allegheny County spokesperson said, "County 9-1-1 has received three separate calls reporting that there is an active shooter in three separate schools. We are also aware that similar reports are coming in for schools outside of the county. In each instance, law enforcement is responding but believes that these are false reports. Thus far, there has been no active shooter found and no injuries at any school. Law enforcement will continue to thoroughly check out any reports."This situation appears to have impacted schools in multiple counties.New Castle police said they received a phone call from a male threatening to shoot up New Castle High School. The school was immediately put on lockdown, and NCPD units were all on the scene within minutes. The school was cleared by law enforcement and New Castle Area School District personnel, and the lockdown has been lifted.In addition, Hopewell High School in Beaver County received a similar call, as did Laurel Highland High School in Fayette County.A statement from FBI Pittsburgh said the agency "is aware of the numerous swatting incidents wherein a report of an active shooter at a school is made. The FBI takes swatting very seriously because it puts innocent people at risk."The investigation starts with Zone 4 and as it expands they will determine if federal or state charges will apply to the person or people responsible."It continues to tell us the the days and times we live in. all of us have to be responsible for each other to make a difference and I think you've seen that today," Mayor Ed Gainey said.