A tugboat pulling heavily loaded barges hit six moored tour boats, sinking one and injuring a woman, on the Chao Phraya River in Bangkok on Wednesday.
The accident occurred near Krungthep Bridge in Bang Kholaem district just before 11am, Rama 199 radio centre reported. The barges were loaded with sand.
Rescue teams, including firefighters, rushed to the river.
News reports said the tug captain seemd to lose control in the strong curent, veering off course and colliding with tour boats moored near the bridge.
Six of the moored boats were damaged. One, a 40-seater, sank. An injured woman with a swelling on her head was taken to hospital, reports said.
The Marine Department and police were investigating.