A Massachusetts state trooper was injured Wednesday evening after his weapon accidentally discharged at the Mounted Unit barn in Acton, according to State Police.

First responders transported the trooper to Lahey Hospital in Burlington with injuries that were not life-threatening, police said. The trooper was released from the hospital overnight and is recovering at home. 

Police say that per policy, he will be out on administrative leave. The matter remains under investigation. 

The Mounted Unit conducts patrols on horseback at state parks, beaches, and reservations with the mission of providing safe and family-friendly environments for visitors.