A cyclist who was killed in a crash with a ute in Sydney's north was believed to be riding the wrong way along a road when he was struck, police say.
The 24-year-old man, from Finland, died at the scene of the crash on Nioka Road in Narrabeen on Thursday.
Police said the cyclist was believed to be riding north in the south-bound lanes about 11am when his bike and a Mitsubishi ute collided.
The driver of the ute was taken to hospital for mandatory blood and urine testing, and the vehicle was seized for mechanical examination.
"Investigators believe that the cyclist was travelling north in the southern lanes but have appealed for anyone who witnessed the incident and has not yet spoken to police to come forward," police said.
Nioka Road was closed between The Esplanade and Veterans Parade for several hours while police examined the crash scene.
Anyone with information about the crash has been urged to call Crime Stoppers on 1800 333 000.