A 19-year-old Calgary man arrested after a fatal crash on B.C.'s Sea to Sky Highway Saturday has been released from custody.

In a written statement released Monday, police say the investigation into whether the man was impaired by drugs is continuing.

"Impaired driving by drug investigations are complex and challenging," said RCMP Sgt. Peter Thiessen.

"In an effort to ensure the strongest case possible, there is more evidence to be gathered. Once that evidence is obtained, investigators are confident that the investigation will move forward in a positive manner."

The 19-year-old, whose name has not been released, was arrested after his Ford pickup truck allegedly crossed the centre line on the Sea to Sky Highway at Cheakamus Lake Road, about five kilometres south of Whistler, crashing into a limousine going the opposite direction.

Sea to Sky Highway at Cheakamus Lake RoadSea to Sky Highway at Cheakamus Lake Road

The limo exploded and was engulfed in flames, killing the driver and lone occupant, 54-year-old Shafiqur Rahman.

Harman Sanghera, the fleet manager for Aerocar Service, urged anyone who was with the suspect driver to call police.

"Anybody who may have been socializing with the individual, anyone who may have been driving up to the Sea to Sky Highway, any person who may have been working at an establishment who may have served this individual on this night — please come forward."

Sanghera called Rahman one of the company's elite drivers, saying he had never had an accident or speeding ticket.

The crash is being investigated by the Lower Mainland District RCMP Traffic Services and the Integrated Collision Analysis and Reconstruction Service.