AN investigation has been launched after a man collapsed and died after taking a so-called 'legal high'.

Detectives from Sussex Police are probing the death of the 21-year-old man from Worthing, who is suspected to have taken a so-called 'legal high' in the time leading up to his death.

The man, from Worthing, was seen by a passing driver to be very unsteady on his feet as he walked in Cissbury Ring in Findon.

The witness told police she saw him fall over in Central Avenue, get up and then fall over again.

After going to his aid, she alerted the emergency services to the medical incident shortly before 5pm on Saturday (May 7).

The man was taken to Worthing Hospital where he died at 7.30pm that day.

Detective Sergeant Simon Dunn, of Sussex Police, said: "We are awaiting results of a post mortem and toxicology tests.

"We are keeping an open mind regarding the events that led up to his untimely death."

Anyone who may have seen the man in the Findon area in the time leading up to him collapsing is asked to contact Sussex Police via email 101@sussex.pnn.police.uk or call 101 quoting serial 1457 of May 7.