Dee Why, Sydney: Grim theory emerges after body found in carpark

Investigators are probing a distressing theory about the death of a man whose body was found in the car park of an apartment complex in a ritzy suburb.

Emergency services discovered the 40-year-old man's body on Ilikai Place in Dee Why, on Sydney's Northern Beaches, at 7.11am on Monday following a report from a member of the public.

The riot squad and paramedics spent four hours trying to enter a unit in the complex to speak with a 41-year-old man allegedly known to the deceased and also to police.

He was arrested at about 12.30pm that day and taken to Manly Police Station for questioning. No charges have been laid.

Acting Commander Traci Watt from the Northern Beaches Police Area Command confirmed the death is being treated as suspicious but not as a murder.

A line of inquiry police are pursuing is whether the man suffered a drug overdose before his body was dumped in the garage.

'We will be waiting on the results of the autopsy to understand how this gentleman died,' Mr Watt said.

He added that initial investigations revealed the man showed no signs of injuries.

The man arrested at the unit obscured his face with a green hoodie while being walked to a police car.

A neighbour described seeing a black hatchback approaching the unit complex multiple times before 5am on Monday morning.

A next-door neighbour of the dead man told Daily Mail Australia the unit complex was generally a quiet place to live.

‘I didn't hear or see anything, it’s usually a pretty quiet building,’ local resident Kassan said.

‘It’s a very, very scary thing to happen. I've lived in the building eight months and found out about it when the police arrived this morning.’

Anyone with information is being urged to contact Crime Stoppers.