A MAN charged over an alleged street race that killed an elderly couple last year has been found dead in his car, police say.
The 28-year-old Glenmore man had been charged earlier this month, along with another 28-year-old man, over the accident in which Alan and Judith Howle died at St Marys on July 29.
Two Holden Commodores and a Mazda were allegedly racing when two of the vehicles rammed into the couple's car at an intersection.
Mr Howle, 71, and his wife Judith, 70, died at the scene.
Police said the Glenmore man was found dead in his car on St Thomas Street, Mulgoa, soon after midday yesterday.
They would not confirm reports that he had been informed the charges against him were to be upgraded to manslaughter.
Police said an internal inquiry had been launched and a report was being prepared for the coroner.
"The NSW Coroner has directed that a critical incident investigation team be established to examine the circumstances surrounding the man's death," police said.
"Police believe there are no suspicious circumstances involved."
The dead man, alleged to have been driving the blue Mazda, was first charged with dangerous and negligent driving and taking part in a road race. He was on bail and due to appear in Penrith Local Court on March 17.
Robert James Borkowski, 37, remains in custody over the incident, on charges including manslaughter and aggravated driving causing death. Police allege Borkowski was at the wheel of the second Commodore.