A 76-year-old moped rider sustained critical injuries in a collision in Mililani Tuesday, Honolulu police said.

A Toyota multi-purpose vehicle driven by a 47-year-old man was traveling westbound on Meheula Parkway at about 12:15 p.m.

The vehicle slowed to turn right into the driveway entrance of Mililani High School when it was struck by a Zhong moped that tried to overtake the Toyota, police said.

The Toyota driver was not injured and remained at the scene.

Police said the moped rider was taken in serious condition to a hospital. While there, his condition worsened to critical condition.

Police noted the rider was not wearing a helmet at the time of the crash.

It’s unknown at this time whether speed was a factor. Drugs and alcohol were not factors.