Channel Tunnel services between England and France were disrupted on Friday when about 150 migrants living in the Calais area in northern France occupied the tunnel, blocking and disrupting services in a bid to board U.K.-bound trucks.

Freight and passenger services were delayed after migrants hoping to enter the U.K. attempted to access restricted areas on the French side, according to a Eurotunnel spokesman. "Eurotunnel reiterates its call to the authorities to provide a solution to the migrant crisis and restore order to the Calais region," he said, according to the Independent.

Dan Cook, operations director at transportation and logistics company Europa Worldwide, said “marauding mobs” were breaking into the company’s vehicles.

“This isn't in lay-bys off the beaten track at night, this is in broad daylight on the motorways approaching Calais and what you see, to be blunt, is marauding mobs around trailers ... climbing on board, breaking open backdoors with broadly no sign of any sort of policing to prevent it,” he said, according to the BBC.

The incident comes a week after migrants took advantage of a wildcat strike in Calais to try to board trucks bound for the U.K., underscoring the worsening migrant crisis around the transportation hub. Around 3,000 displaced migrants from countries including Eritrea, Sudan, Syria and Afghanistan are living around Calais -- the closest town on the European mainland from the U.K. -- in camps.

Aid workers have decried the increasingly desperate situation in these camps, warning that shortages of food and water were forcing migrants to take increasingly risky measures while attempting the crossing to U.K.

British Home Secretary Theresa May on Thursday called on French authorities to step up their security to restrain the illegal passage of migrants. Paris and London reportedly agreed to prevent future ferry strikes, which authorities said only encourages migrants to attempt the crossing. “What we have agreed today is a further working with the French government to ensure we can return people from Europe into Africa so that people see that actually that journey does not lead to settlement in Europe,” May said, according to Euronews.