NORWALK - A sunken houseboat is being blamed as the source of a strong chemical odor that has been reported along the Norwalk River.

The Norwalk Fire Department says it responded to reports of a strong odor near the Oyster Bend Marina on Charles Street.

Fire officials say the houseboat sunk and leaked nearly 50 gallons of gasoline. They say the spill was confined to the area around the boat because of the ice in the river.

Crews are saying that they expect the cleanup will take close to a week to complete. They say they have removed all harmful fluids and are working to clean up any gas that is left.