Groton — Coast Guard crews responded to a 25-foot vessel that became disabled on the Thames River near Eastern Point Beach at about 1:15 p.m. today when the engine overheated.

Steven Spilious , petty officer second class, said the incident was initially reported as a boat fire, but upon arrival crews learned that the boat had overheated and that there was a small explosion on board. A Coast Guard patrol boat was nearby at the time so was able to respond to the call quickly, he said.

The boat was carrying four passengers and a dog. No one was injured.

Spilious said three passengers were taken aboard the Coast Guard vessel and brought to shore. The owner stayed on his boat while a fellow boater towed it to Noank Shipyard.