Five people and a dog had to be rescued from a sinking narrow boat on the River Thames, police have said.
Emergency services were called to a stretch of the river near to Canary Wharf, east London, after reports the vessel, called Mini Moo, was taking on water at around 5.30pm on Friday.
Officers from the Metropolitan Police Marine Policing Unit arrived within two minutes and helped three people and the dog out of the water.
Two more people had to be rescued by the crew of a London RIB Experience boat.
The boat's female owner and four men were described as being in "shock" from the cold water and were taken to hospital as a precaution, but subsequently discharged. The dog, named Gus, was also uninjured.
A spokesperson for the Metropolitan Police said the vessel sank completely within minutes of it starting to take on water.
Inspector Tania Martin, of the Marine Policing Unit, said: "The Thames is a dangerous river, especially in mid-flow where the tidal stream can carry a person away below the surface in seconds.
"The five people were not wearing lifejackets, were weighed down with shoes and clothing, and were in shock from the cold water and a vessel sinking.
"What appeared to be a relatively safe hop across the river between marinas had turned into a potentially life-threatening situation in a matter of seconds.
"Both RIB Voyages and police crews recognised the potentially fatal situation and demonstrated great composure and control to carry out this rescue."