A Rockville police officer and member of the Maryland National Guard has been charged with possession of child pornography, law enforcement officials said. He was detained Friday while serving at the Six Flags coronavirus vaccination clinic in Prince George’s County.

Daniel Joseph Morozewicz, of Frederick, is suspended with pay from his job at the Rockville City Police Department for an unrelated personnel matter, officials said.

Morozewicz has worked for the police department since July 2013 and was suspended in October, police spokeswoman Andrea Escher said. She declined to say why he was suspended.

Morozewicz, a corporal in the Maryland Guard, had been assigned to 1st Battalion of the 175th Infantry Regiment, which was assisting with vaccine distribution.

He has been removed from active duty, according to Maj. Kurt M. Rauschenberg, a Guard spokesman. Morozewicz joined the Guard in February 2015.

“The Maryland National Guard takes these situations seriously and will cooperate with law enforcement agencies as needed,” Rauschenberg said in a statement.

The Frederick County Sheriff’s Office said detectives monitored Morozewicz from Sept. 8 to Dec. 30, and found he downloaded images and videos of nude girls engaged in sexually explicit conduct. The joint investigation was conducted by the Internet Crimes Against Children unit of the sheriff’s office and the Baltimore field office of the Department of Homeland Security’s Homeland Security Investigations.

The U.S. District Court for Maryland on Feb. 23 issued a federal search warrant of Morozewicz as well as his home and vehicle, and detectives at about 9:15 a.m. on Friday detained him at Six Flags, according to the sheriff’s office. Authorities said he was later charged with one count of possession of child pornography.

He was transported to the Frederick County Adult Detention Center for booking, where he posted bond and was released on his own recognizance. The investigation is ongoing.

Attempts to reach Morozewicz on Saturday were unsuccessful, and online court records did not identify his lawyer.

The Frederick County Sheriff’s Office asks that anyone with information contact Detective Joe McCallion at jmccallion@frederickcountymd.gov or 301-600-1022.

Jennifer Jenkins contributed to this report.