Eurotunnel services have resumed after halting for a night Friday, because an organized group of refugees broke into the railway service’s French terminal at Calais, a port city in northern France. The BBC reported that trains were halted from 11:30 p.m., local time, Friday (6:30 p.m. EDT) after a group of 200 migrants tried to manhandle staff and throw stones at them, in their attempt to enter the terminal.

According to the Telegraph, the French authorities were trying to stop the invasion and evict the refugees from the terminal, which led to the suspension of all passenger and freight services through the tunnel. The Guardian reported that the Eurotunnel website announced the resumption of railway services at 8.30 a.m., local time, Saturday (3:30 a.m. EDT) and passengers on both sides of the channel were informed to expect 30-minute delays in train services.

A large number of refugees reportedly arrived in a well-organized manner, and about 100 of them managed to break into the terminal. According to the BBC, one staff of Eurotunnel and two police officers were injured during the incident. Police have reportedly arrested up to 100 people.

A Eurotunnel spokesman told the Guardian: “It’s a massive invasion and intrusion by a very large and coordinated group of migrants. They are being gathered up by the police authorities.”

According to the Telegraph, an estimated 5,000 migrants displaced from countries, like Syria, Libya and Eritrea, are currently camping in and around Calais, with an aim to enter Britain, and around 150 people try to get into its terminal each night.

The Eurotunnel company had only recently installed more security measures to prevent refugees from entering the tracks, driving migrants and refugees to resort to more desperate measures.