Manassa was allegedly attacked by two men in the driveway of a home on Driftway Drive in Pemulwuy, at 10.45pm on June 26.
He had just arrived at the home with his girlfriend, NSW Police said. 
The 21-year-old suffered stab wounds in the attack. He then got into his car and drove a short distance before succumbing to his injuries.
Paramedics treated the man, however, he could not be revived.
Detectives executed multiple search warrants yesterday morning at homes in South Penrith, Mt Druitt and Woodcroft.
Police allege they found a getaway car at one address in Woodcroft. 
A 17-year-old man was arrested from the home in South Penrith.
He was taken to Penrith Police Station where he was charged with murder.
The man was refused bail and will appear in a children’s court today.
A 16-year-old male was arrested from a home in Mt Druitt.
He was taken to Mt Druitt Police Station, where he was also charged with murder.
He was also refused bail and will appear in a children’s court today.
Investigations are continuing. 
