KENNEBUNK, Maine (WGAN)  The U.S. Coast Guard says they are investigating after a tugboat sank about three miles off the coast of Kennebunk.

The Coast Guard says two tugboats collided Thursday morning.  Crews were able to tow one of the boats to a Coast Guard station in Portsmouth, New Hampshire, but the second boat sunk as it was being towed to Portland.

The Coast Guard says that boat, the 80-foot Capt Mackintire, sunk in 158 feet of water.

The Coast Guard says it is working with federal, state and local authorities to evaluate potential pollution and respond to reports of sheening in the area where the tug sank.

The Coast Guard says they’re also investigating the cause of the collision.