The ferry company P&O has called on French police to improve security at the port of Calais after hundreds of migrants scaled fences and scrambled through a security gate in a bid to board the vessel bound for Britain.
Witnesses said staff were forced to turn water cannon on the group as they attempted to gain entry to the MyFerryLink Berlioz ship by running up the boat ramp.
Remarkable footage, which was filmed and uploaded on to YouTube by an eyewitness called Mark Salt, showed what has been described as "unique" scenes in which scores of migrants sprint across the port in an attempt to evade port officials.
The captain of the P&O ferry Spirit of Britain said he witnessed a "large group of migrants running towards the berths" yesterday afternoon, which he "estimated at around 100".
Earlier, a further 85 migrants also forced their way through a gate at the port and fences before being detained by police.
A spokesperson for P&O Ferries said: “We are of course concerned that it might happen again and we have seen some extraordinary events over the last few peak weekends with migrants running amok on the motorway outside the port when queues have formed prior to the UKBA controls.
“They have tried, often successfully, to gain access to freight vehicles and have also been targeting caravans and motorhomes. We have asked the French authorities to do more to prevent such interference.”
The captain of P&O ferry Spirit of Britain, who witnessed Berlioz crew members dousing the throng to prevent them boarding, was told by port authorities to wait in the inner harbour until police arrived.
Passenger John Bailey, speaking to the BBC, said he was "shocked to see a huge crowd of migrants on the main access road who were being guarded by about 20 French police - some armed with sub-machine guns".
"This was clearly no deterrent as they obviously ran past them into the port, which must have been a distance of about a mile," he said.
A UK Border Force spokesman said the ramps on the vessel were immediately raised when the migrants entered the port, and none were able to board.
She said: "The incident was quickly brought under control and the French police apprehended all those involved. All freight vehicles inside the port at the time have been rescreened by Border Force."
On Tuesday, the mayor of Calais, Natacha Bouchart, said she would blockade the port unless Britain helped to control the migrants, claiming her city had been “taken hostage” by more than 1,000 migrants attempting to cross to the UK from France.
Mrs Bouchart, a centre-right politician, has claimed Calais is in a "state of emergency". The migrants - Eritreans, Ethiopians, Sudanese, Afghans and Syrians - are desperate to reach Britain where some have family or because they speak a little English.
In recent months the situation in Calais has deteriorated. Makeshift camps now house an estimated 1,300 to 1,500 people, affording little shelter to the elements and with crime and violence prevelent.
MyFerryLink, speaking to the Guardian, confirming the incident and saying: "The crew took immediate action to ensure the ship's security and the attempt was unsuccessful."