When France shut the Calais shanty town known as the Jungle in 2016, migrants seeking entry to Britain were forced to look for less safe passage up the coast in Belgium - the route taken by a truck in which 39 bodies were found this week. Belgium's federal prosecutors, who handle cases of terrorism and organized crime, said on Thursday they had opened an investigation into the deadly transport. Initial findings showed the truck passed through the Belgian cargo port of Zeebrugge, from where it crossed by ferry to Britain. The victims — 31 men and eight women, all believed to be Chinese nationals — were found in a refrigerated truck on an industrial estate 20 miles (32 km) east of London. The driver was detained on suspicion of murder. Belgian prosecutors said they were looking into when and where the victims were loaded into the container. Regional British police said a case of human trafficking was suspected. This was not the first fatal migrant transport routed through Zeebrugge — a container with the bodies of 58 Chinese inside found in the English port of Dover in 2000 had also come from the Belgian port. However, in recent years the focus of migrant efforts to reach Britain was the French port of Calais — across the Channel from Dover — offering more than hourly ferry services and an undersea tunnel on the shortest crossing to the United Kingdom. The migrant community in Calais grew to some 6,000 people, most of them in a shanty town dubbed the Jungle, outside Calais until French authorities emptied it in October 2016, saying it was a security and health hazard. Cast adrift and driven away from Calais by the Jungle's closure, many migrants looking for the next closest passage points made their way north to neighbouring Belgium, said Stef Janssens at that country's federal center of migration. "There was a shift of the route to Britain from Calais to Belgium's E40 highway," he said, with people trafficking gangs taking control of parking spots where migrants congregate along the motorway leading from Brussels to the North Sea coast. In contrast with Calais, Zeebrugge largely handles cargo with far fewer leisure travelers. Dogs and heat scanners are used to detect stowaways though they might not be spotted in sealed, refrigerated containers like the one in which the 39 bodies were discovered this week. In 2014, an Afghan migrant was found dead in a container that had arrived in the British port of Tilbury, along with 34 who had survived. This also had gone through Zeebrugge, but at a time when the scanner was not working. "If they had to open up every container or every truck... there would be trucks (queued up) from here to Brussels. Every day there are 4,000 trucks coming to this port," Dirk de Fauw, mayor of the city of Bruges and chairman of adjacent Zeebrugge, told Reuters television. Smugglers remain on the E40 motorway, Janssens said, but in their hunt for spots with weaker port controls and security, they had headed even further north in the past two years. "This has also shifted to Antwerp and ports such as Hook of Holland in the Netherlands because these ports are used less and subject to lesser controls," Janssens said. Smuggling migrants is lucrative, he said, with migrants charged up to 6,000 euros ($6,690) for "guaranteed" passage to Britain. The Geneva-based International Organization for Migration (IOM) says it has noted a trend in the past year of increasing numbers of migrants also trying to cross to Britain in small boats. There were five drownings in the Channel this year. The 39 deaths this week brought the total number of fatalities among migrants crossing the European continent to 97, compared with 92 at the same juncture in 2018. — Reuters