Lancaster police are investigating an incident where a gunshot was fired on the playground of the Martin Luther King Elementary School.
The school at 455 South Duke Street went into lockdown after the incident at 2:48 p.m.
No students were on the playground, and there were no reported injuries and no damage to property, police said.
Police said an anonymous caller reported that two males had been in the playground area when one of them fired a single shot from a handgun and both ran east on Green Street from the area of Rockland Street.
Responding officers found a single spent casing on the southwest corner of the playground, but did not locate the suspects.
Anyone with information is asked to call Lancaster police at 717-735-3300 or Lancaster City-County Crime Stoppers at 1-800-322-1913.