Extensive damage has been done to a Sarnia marina and four people are facing charges, police say.

Damage is estimated at $200,000 after police say copper wiring was stolen from the Andrew S. Brandt Marina on Seaway Road.

Marina employees and Sarnia Parks and Recreation staff contacted police last week.

Police say numerous planks had been removed and large amounts of conduits containing copper wire were cut from under the docks, heading out to the marina.

Police set up surveillance in the area of the marina last Friday in an attempt to locate those responsible.

Police say around 2 a.m., an officer saw a vehicle in the area and observed four people approach on foot with various tools.

Other officers were called in and surrounded the marina, police say.

The four suspects, all from Sarnia, were arrested without incident.

They are facing charges of break and enter, possession of break-in tools and mischief over $5,000.

Police say two were also charged with possession of drugs.

Police believe another break-in occurred during Easter weekend and damaged the docks further.

Marina operator Dave Brown called the damage "despicable."