Police are investigating after the body of a man was found beside a motorway near Byron Bay in Far North NSW.

Events began at 7.15pm yesterday when emergency services were called to the M1 Pacific Motorway, near Billinudgel, after three cars crashed into a motorcycle.

A member of the public told officers they had found a body believed to be the male rider nearby.

The man is yet to be formally identified.

Three drivers were taken to hospital for mandatory testing, and a crime scene was set up.

Police crash investigation experts were called and began an investigation.

All vehicles were seized for forensic examinations.

A report will be prepared for the coroner.