内容摘要："I can hear mothers crying, friends, because their children are still inside the building. It's desperate to watch," the woman - a teacher - said.

"I can hear mothers crying, friends, because their children are still inside the building. It's desperate to watch," the woman - a teacher - said.

In the same period, net EU migration was -95,000, meaning 95,000 more EU nationals left the UK than arrived.Net migration of British nationals was -21,000, meaning more British people left the UK than came back.

When a walker called 999 to say he had seen a body in a wetsuit floating in a remote reservoir, detectives got to work.Search teams combed the barren marshland on foot near to where he was found while a helicopter and drones searched for any clues on how and why he got there.Investigators have asked UK police forces to check their missing people registers and have spoken to Interpol because the area can be popular with tourists.

Despite forensic tests, extensive inquiries and searches and appeals for information, detectives still have not solved the mystery of the man in the wetsuit.He was found just before 08:30 on a Friday morning last October in the eerily still rolling mid-Wales countryside.

Investigators suspect he might have been in the vast Claerwen Reservoir for up to 12 weeks - so could have been in the water since as far back as July and in the height of summer.

What police say is "highly unusual" about the man in the wetsuit is that no evidence of his personal belongings or an abandoned car or bike were ever discovered.James Malley, a research technician, operates a machine that can work out how much oxygen is contained within the specs of dust.

He shows us a test run of what he will do."I'm going to hit that grain on the tray with a laser," he says, showing the scene magnified on a computer screen.

"It's going to start to glow, and you will see it melt inwards," he says.The team has a year to finish their research. By the end, their search for answers will probably end up destroying the samples.