Published: Mar 26, 2013 2:53 PM EDT

FORT MYERS, Fla.- Lee County Sheriff's deputies are investigating 17 boat burglaries at the Port Sanibel Marina, reported on Monday. The value of the stolen property is estimated at $85,000.

The general manager told deputies that someone had taken the GPS devices from 17 boats between 4:30 p.m. on Sunday and 3:00 p.m. on Monday. Three of the boats are located outdoors. The rest are located in a boat den.

Security officers were on duty at the time.

The investigation continues.