A 29-year-old man died in a single-vehicle collision Friday evening after he veered off of Kamehameha Highway in the Kualoa area and struck a rock retaining wall.

The Honolulu Police Department said the collision took place at around 8:40 p.m. Friday as the man was driving northbound on the highway.

The man, who wasn’t wearing a seat belt at the time, was transported to an area hospital in critical condition and later died from his injuries.

It isn’t yet clear if speed, drugs or alcohol were factors in the collision.

The traffic fatality is Oahu’s ninth of 2023. There were seven at this time last year, HPD said.