IT HAD all the hallmarks of a gangland murder but as investigations into the disappearance of a Sydney drug dealer deepened, police learned the suspects they were hunting had once served beside them.
Former NSW detective Glen McNamara was behind bars in protective custody on Monday night, charged with the murder of 20-year-old university student Jamie Gao.
Disgraced NSW police officer Roger Rogerson, who has served two jail terms for lying to the police watchdog, was still being sought for questioning.
A body, which had not been formally identified but was believed to be that of the missing student, was discovered wrapped in a tarpolin, off Shelley Beach in Mr McNamara's home suburb of Cronulla early Monday.
When Mr Gao was reported missing last Wednesday, police launched a public appeal amid "grave concerns" the Asian national had met with foul play.
Friends and family had told police Mr Gao had been excited about a meeting that was to take place on Tuesday night but that no-one had heard from his since.
Investigations led police to raid Mr Rogerson's Padstow home at the weekend where they seized a silver car and other items.
Mr McNamara was arrested during a traffic stop at Padstow on Sunday.
He fronted the Kogarah Local Court briefly on Monday and was refused bail.
Police allege the royal commission whistle-blower was present when Mr Gao was killed nearby on Tuesday night.
Speaking to reporters in Sydney on Monday, Detective Inspector Luke Moore said police believed Mr Gao had taken 3kg of methamphetamine to the meeting but that the "substantial" drug transaction had gone wrong.
He said Mr Gao had got into a white car with two men before being driven to a secret spot and killed.
He could not confirm whether a boat, seized along with the white car suspected of being driven to the crime scene on Tuesday, had been used to dispose of Mr Gao's body.
Mr Gao's mother was overseas when her son was reported missing.
Det Insp Moore said she had since returned to Australia and police were working to support her and her family.
Mr Rogerson, 73, was a well-known figure in NSW in the 80s.
The former decorated officer had received a string of bravery medals and was well respected until he was dismissed over the shooting death of a Sydney drug dealer.
He was acquitted on charges relating to drugs and conspiracy to murder.
Sydney homicide detectives travelled to Brisbane where Mr Rogerson was believed to be staying on Monday.
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