THE port of Calais was shut down for almost two hours today after migrants were spotted swimming in the sea as they tried to get aboard UK-bound car ferries.

"It’s a tactic that we haven’t seen much of in the past, and it shows the desperation of those involved," said one dock worker.

5 Diving for Dover . . . Migrants from Calais have been spotted swimming in desperate attempts to board ships bound for Britain Credit: News Group Newspapers Ltd

5 Cars line up and police are on standby after Calais port was shut down for almost two hours today Credit: Splash News

"Migrants are risking their lives in the middle of the night, and everything had to be done to ensure their safety.

"All traffic was halted at 2.20 in the morning, as a search and rescue operation got underway, with helicopters and boats involved.

"Those plucked out of the water were rushed to hospital, and traffic was not allowed to move again until past 4am."

Customs boats, fishing vessels and other crafts were also involved in the search for migrants in the water, indicating the extent of the problems.

5 The Home Office revealed over 7,000 people have made their way to Britain via ferry ports Credit: Times Newspapers Ltd

5 Security has been improved in the port and around the Channel Tunnel Credit: News Group Newspapers Ltd

Up to 5000 migrants are currently living rough in the Calais areas as they try and get to Britain, where they will claim asylum, or disappear into the black economy.

Security has been improved in Calais port, and around the Channel Tunnel, leading to migrants making more desperate attempts to reach Dover.

Figures released last month show that the number who successfully smuggled themselves across to England on ferries more than doubled in the past three years.

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Ministers disclosed that the number of ‘clandestine entrants’ who made their way into Britain through Dover and other ports has risen from 1,432 in 2013 to 2,935 last year.

Experts said that the true figures are likely to be significantly higher as many illegal immigrants disappear after entering the UK.

Lord Green of Deddington, the chairman of Migration Watch UK who obtained the figures, said last month: ‘Despite all the efforts that have been made to tighten up security in Calais these figures show that the number getting through and later detected has doubled in three years.

5 Desperation . . . Up to 5,000 migrants are living rough in the Calais area as they try to get into Belgium and Britain Credit: Reuters

"There are bound to be others who are never detected and simply disappear.

"This points to the likelihood that there are similar inflows from Belgium and Holland and indeed from other French ports."

The Home Office revealed that over the past three years more than 7,000 people have made their way into Britain through ferry ports.

Just over half of them were caught at ferry ports, while the remainder were discovered elsewhere in the UK.

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