Two hitchhikers have been killed in a horror crash on the New South Wales mid-north coast.

Police say the two teenagers were hit by a four-wheel drive on the side of the Oxley Highway at Sancrox, near Wauchope, about midday on Sunday.

Nineteen-year-old Kane Bramble, from Port Macquarie, and 16-year-old Wauchope local Clint Ritchie died at the scene.

The driver failed a roadside breath test but blew under the limit at Port Macquarie police station.

The 37-year-old has been released but police are continuing to investigate.

Relatives of both teens visited the crash site today, expressing concern and anger that the driver has not been charged.

Inspector Paul Fuller says specialist officers are still working to pinpoint exactly what happened.

"The Crash Investigation Unit, they're in charge of inquires and they'll conduct all the investigations into how the accident occurred," Inspector Fuller said.

"I believe there were a number of witnesses who were travelling in the same direction as the Nissan Patrol.

"There were witnesses, a number of people stopped and assisted the two young men at the time and the police have spoken to a number of witnesses who saw the collision occur."

Neil Porter from Port Macquarie-Hastings Council says the community is in shock.

"My heart and sympathies go out to the families of these two young gentlemen that were killed in this terrible accident," Mr Porter said.

"It's a stretch of road that over the years has been identified as one that needs to be upgraded.

"To their credit the State Government have spent a lot of money taking out the windy parts of that road to improve safety."

A resident living near the accident site, Donna McHugh, says crashes on the road are still a regular occurrence.

"It's constant. It's three in the last five weeks, serious accidents, in the 300-metre stretch of road," Ms McHugh said.

"There is room to straighten the road, lower the speed limit, put kangaroo fencing up. There are many, many things that can be done."