A man who crashed his car after hitting an object on the road panicked when he returned to the scene and discovered he had run over a man, Invercargill District Court was told today.

The man, farm worker Tom Fry, 18, was killed in a crash at Richmond north of Oamaru, on State Highway 1 in the early hours of May 13. It appears he was struck at different times by two vehicles but exact details of what happened have not yet been revealed.

In court today Cam Paul Kennedy, 25, admitted one charge of wilfully attempting to obstruct the course of justice, by taking all identification from, then burning, a vehicle. Other charges relating to the incident were withdrawn.

Police prosecutor Sergeant Penny Stratford told the court that emergency services attended the scene of the crash but Mr Fry died. There was evidence another vehicle had crashed into a road sign but it had left the scene, Mrs Stratford said.

About the same time, Kennedy and a female passenger were travelling in the southbound lane of the same stretch of highway, when the vehicle hit an object.

Kennedy lost control of the car and crashed off the road. When he checked to see what he had hit, he realised it was a person.

Kennedy then drove his Nissan Skyline car for 15km through the back roads before he crashed it. He removed all identifying features from the car including the registration plates and window labels, before pouring oil over the car and setting it on fire.

The pair then walked to a farmhouse where they used the phone to contact an associate. They were picked up and on the trip back to Invercargill Kennedy threw the registration plates out the window. Once home, he burnt his clothes and two cellphones.

Defence counsel Kate McHugh said Kennedy had panicked when he saw he had run over a person.

He was remanded on bail to appear for sentencing on October 21.

Last month, a commercial truck driver was charged with careless driving causing the death of Mr Fry.

The 35-year-old Timaru man was also charged with attempting to obstruct the course of justice by lying about the cause of damage to his truck and lying about whether or not he drove through the intersection of York St and State Highway 1; failing to stop and ascertain injury after a crash; and failing to report a crash.

He will appear in Oamaru District Court on Wednesday.