Part of airport was evacuated and 21 people fell ill but police found no sign of any hazardous material
Update: Man arrested on suspicion of bringing teargas to Heathrow
Police were called to Heathrow late on Monday afternoon when 21 people fell ill in Terminal 4. Initial reports suggested a hazardous material could be involved and part of the airport was evacuated. But when the emergency services conducted a thorough search, no trace of any adverse substance was found.
A source within the Metropolitan police subsequently suggested the event could be something quite different – a case of mass hysteria. And some experts agree.
“What happened at Heathrow is almost certainly an episode of mass psychogenic illness that is anxiety-based,” said Dr Robert Bartholomew, a University of Auckland sociologist who is an expert on the subject.
