Major Crime Detectives are investigating the circumstances surrounding the death 48-year-old male in Darwin City yesterday.

Detective Acting Senior Sergeant Tony Henrys said Police responded to a report at around 6pm that a man had collapsed in the vicinity of Frogs Hollow near Woods and Lindsay Street.

"It appears the victim was involved in an altercation and assaulted by a group of male and female adults. Police are treating the death as suspicious.

"Police urge anyone who may have witnessed this incident or anyone who may have further information to contact Police on 131 444 or Crime Stoppers on 1800 333 000."