Men walk beside the road leading to a makeshift camp near the French port of Calais, where migrants have tried to storm Channel Tunnel security in attempts to reach Britain. (Rob Stothard/Getty Images)

Britain’s prime minister pledged Friday to send extra fencing and sniffer dogs across the English Channel to the French port of Calais as part of escalating efforts to block desperate migrants attempting to cross to England via the undersea tunnel.

“The situation is not acceptable, and it is absolutely this government’s priority to deal with it in every way we can,” David Cameron said after holding emergency talks in London.

Calais is the latest pressure point for Europe as it struggles with a growing crush of migrants from Africa, the Middle East and Asia plying smuggler routes across the Mediterranean Sea or overland.

Thousands of migrants have perished in shipwrecks and sinkings. Others are stuck in holding sites such as a makeshift camp in Calais known as “the jungle” that is temporary home to about 3,000 people.

For the past few nights, migrants in Calais have stormed fences en masse trying to gain access to the Channel Tunnel, a 30-mile link between France and England. Officials said that Tuesday, migrants made about 2,000 attempts to storm the Eurotunnel terminal. In response, France announced that it was sending 120 additional officers to the area.

A Migrant waits along the fence as he tries to catch a train to reach England, in Calais, France, 30 July 2015. (Yoan Valat/EPA)

Cameron said Friday that he is eager to work “hand in glove” with the French.

Many in Britain say France should be doing more, with some urging the country to deport illegal migrants to their home countries.

But the British government has shied from criticizing France, where British immigration checks are carried out. Cameron’s office said that he spoke about the situation with French President François Hollande late Friday.

Many political commentators interpreted Cameron’s pledges as an attempt to show that the government is addressing a situation without easy solutions.

The crisis has dominated the British news media all week, with the premier coming under fire at one point for calling migrants a “swarm of people.”

“You have got a swarm of people coming across the Mediterranean, seeking a better life, wanting to come to Britain,” Cameron said in an interview.

In response, Harriet Harman, the opposition Labor Party’s acting leader, said the prime minister “should remember he is talking about people, not insects.”

Migrants escape from the French Police as they try to catch a train to reach England, in Calais, France, 30 July 2015. (Yoan Valat/EPA)

Many of the migrants in France are determined to make it to Britain, which remains a magnet for several reasons. They include the perception that it is easier to work illegally in Britain because there are no national identity cards, and the belief that the odds for asylum are higher than in France.

Since the beginning of June, nine migrants have died trying to make the tunnel crossing, including a man believed to be from Sudan who died this week.

Migrants climb aboard trucks and trains heading through the tunnel for Britain in hopes of crossing illegally into the country.

It’s unclear how many slip through, but in the area of Kent, on the English side, social services say they are struggling to cope with the increase in children seeking asylum in recent months.

“The biggest problem we have at the moment is the number of 16- and 17-year-olds coming over,” Peter Oakford, Kent County Council’s cabinet member for children’s services, told the BBC.

If migrants don’t get through and are caught by the French police, they are later released and often try again.

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Today’s coverage from Post correspondents around the world