A 20-year-old man has died after being apprehended by a police officer in an east London shop.
The Met Police said the man was followed on foot after officers tried to stop a car in Kingsland Road, Hackney, at 01:45 BST on Saturday.
He was “taken ill” after “trying to swallow an object” and was pronounced dead in hospital a short time later, the force said.
The Independent Police Complaints Commission (IPCC) has been informed.
Footage apparently showing the incident has been shared on social media, along with the hashtag #JusticeForRash.
Police said the officer “intervened and sought to prevent the man from harming himself”.
A force medic provided first aid at the scene before London Ambulance Service paramedics arrived.
Police said next of kin had been informed and a post-mortem examination and formal identification would be “arranged in due course”.
“The Directorate of Professional Standards and the Independent Police Complaints Commission have been informed and have declared the incident independent,” a force spokesman added.