Officials say five bird houses were tossed into a fire pit at a New Jersey farm preserve, killing some birds and injuring others.

Hopewell Township Police Lt. Chris Kascik tells NJ.com the incident is disturbing and police are asking for anyone who has information for the investigation to step forward.

Kascik says a resident reported the incident on July 5 after finding the charred remains of five houses at a fire pit in a picnic area at St. Michaels Farm Preserve.

Bird lovers typically build colonies of bird houses meant to attract purple martins.

Authorities are investigating the incident as arson and police have notified state wildlife officials and township fire investigators. The Mercer County Wildlife Center is caring for five surviving purple martins.