Four people have been taken to hospital after the upper deck of a car ferry collapsed.
Paramedics, police, fire crews and the coastguard were called to the incident at the Fishbourne terminal on the Isle of Wight at around 10.30pm on Friday.
In a statement, Wightlink ferries said: "As part of the usual disembarkation process, after vehicles on the lower deck had left the ship, the starboard forward mezzanine deck with nine cars on board was lowered.
"When it was a short distance from the deck below, it dropped a few feet and made contact with the lower deck."
An Isle of Wight Ambulance Service spokesman said: "Four patients required ambulance treatment for a variety of injuries, none of which are believed to be life threatening. All are conscious and breathing.
"All patients have now left the scene and are on their way to the hospital at Newport."
He added: "We are not aware of the nature of the injuries. It is very fortunate that it was only four people injured, all things considered."
Wightlink ferries said a full investigation into the incident is now under way.
"The incident has been reported to the Marine Accident Investigation Branch and Wightlink is fully co-operating with the authorities," it said.
"St Helen, in common with all Wightlink ferries, is inspected regularly by external surveyors. The last independent engineering survey of the ship, including its mezzanine decks, took place in May 2014 during her annual refit."
Portsmouth police warned of delays for people hoping to travel to the Isle of Wight from the city.
A spokesman said on Twitter: "Just liaised with Wightlinkferry (our side), there are delays for those wanting to travel tonight to the IOW due to the earlier incident."
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