Charles County Sheriff’s Office Cpl. Patrick “P.J.” Mann, a school resource officer assigned to St. Charles High School in Waldorf, was found dead inside his personal vehicle last night in Prince George's County.

Mann’s vehicle ran off Route 210 in the Accokeek area of Prince George’s County. The Prince George’s County Police Department is actively investigating his death.

In 2005, Mann began his career with the CCSO working in patrol and in 2008 transferred to the School Resource Unit. He previously worked at Matthew Henson Middle School and J.C. Parks Elementary School before being assigned to St. Charles High School, where he served since its opening in 2014, as well as Mary B. Neal Elementary School.

Cpl. Mann was one of 15 SRO’s working alongside the Charles County Public School system ensuring safety amongst the students, faculty and staff. SRO’s are sheriff's officers assigned to schools in the county through a partnership with the CCSO and CCPS. The responsibilities include ensuring a safe and orderly environment and being a resource for students.

Richard Conley, principal at St. Charles High School, remembers Mann as “an amazing, hardworking and dedicated guy.”

Conley has known Mann for years prior to working closely with him at St. Charles High School since its opening five years ago, daily ensuring the safety and well-being of the students.

“Cpl. Mann was a member of the St. Charles High School family. He was more than a police officer at St. Charles. He taught classes, served as a mentor to our students and helped coordinate many of the youth camps held during the summer,” said Conley in a letter to St. Charles High School parents on Friday. “Members of the school system’s crisis support team are working with our staff today as they grieve the loss of their colleague. We will have additional support for students at school on Monday.”

All of St. Charles High School’s sports practices and basketball games were called off on Friday and rescheduled to ensure the staff and students are okay before the school community is ready to move on. “Cpl. Mann was highly regarded and this is a huge loss for our school community. He was a true force for good for our kids and our school,” Conley said.

“P.J. was a great school resource officer who was dedicated to the safety and well-being of students. He was beloved by everyone who knew him. He was invested in the success of students and was a part of the Distinguished Dozen program in which he dedicated his time to mentoring a select group of students on academics, manners, life skills and so much more. We are in the process of gathering more details, but for now I simply ask that you keep P.J., his family, his school resource family, students and staff with Charles County Public Schools, and his brothers and sisters at the Charles County Sheriff’s Office in your thoughts and prayers,” Charles County Sheriff Troy D. Berry (D) said in a press release.

Commissioners' Vice President Bobby Rucci (D) ordered the county flag be lowered to half-staff effective immediately on Friday. Under his order, the flag will return to full-staff at sunset on the day of Mann's interment, which is unknown at this time.

The PGPD has yet to release any information regarding the incident, although a police officer with the agency was injured when his car was slammed into by another car while he was at the scene on Route 210. He was taken to a hospital and is in stable condition, according to reports.

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