"He was on life support but they had a meeting to decide whether to turn it off. It's heartbreaking. They were all there to say their goodbyes.''
Also killed were Dominic Stehlin, 19, of Mangere, Uesitini Tootoo, 18, of Mangere, and George Lomia, 20, of Manurewa.
Mr Gaga had been home on Friday night when the three friends, all De La Salle College old boys, dropped by his Mangere home, where he lived with his parents, and asked him to go out for a drink.
They were first seen by police speeding along Wiri Station Rd, Manukau, just before midnight on Friday. The Honda Accord sped away from a police car and the pursuit was called off.
The car then increased to speeds of up to 160km/h along the Southwestern Motorway. The youths were seen by a second police patrol, which was overtaken by the car on the Massey Rd off-ramp.
Police say seconds after the patrol abandoned the pursuit, the car crashed into a parked car on Massey Rd.
Residents heard a loud bang - and emerged in their nightclothes to a gruesome scene.
"The car engine was on and the driver was dead,'' said one resident, who asked not to be named. ''[Police] were trying to get the other two out. I saw them cutting off his T-shirt and putting a neck brace on him,'' she said. ``They covered up the car and left the dead people inside.''
Dominic Stehlin, who was thought to have been driving, was about to become a father for the first time.
Another of those killed, George Lomia, celebrated his 20th birthday on March 3. His uncle and caregiver Gum Maaseia said he was a good person who rarely drank alcohol or partied.
"I didn't know he went out. Every time he informs me. George hardly drinks and if he is does he knows his limit. He is a perfect kid, a lovely kid.''
His parents and siblings were flying in from Australia today.
At a press conference, Superintendent Tims said the tragedy was avoidable.
"I have a very simple and passionate message to drivers, particularly young drivers: if asked to stop by police, stop. These deaths are avoidable.''
The Serious Crash Unit is investigating and the Police Conduct Authority has been notified.