Around 170 people have been evacuated from the HMS Belfast tourist attraction after the gangway leading to the boat collapsed into the River Thames.
The Metropolitan police have said that two men were taken to hospital with minor injuries.
Visitors to the ship that is permanently moored on the Thames were evacuated from the vessel and taken by boat to London Bridge Pier.
The London Fire Brigade had been planning a raining exercise on the ship this afternoon, but were instead involved in the rescue of tourists.
The HMS Belfast is part of the Imperial War Museum, whose spokesman explained that the injured men were contractors who had been working at the site.
According to the museum's website, two contractors working on the site 'have sustained minor injuries and have been taken to hospital as a precaution'.
The ship has been closed until further notice while the museum carried out an 'urgent and full investigation' into exactly what happened.
The statement added: 'At the moment our priority is ensuring all our visitors are safe.'
The museum website explains that HMS Belfast experience shows you what it was like to live and work on board a warship, with nine decks to explore, and battle stories from the Second World War and beyond.
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