A 59-year-old man and his passenger were hospitalized Sunday night following a crash on Diamond Head Road that left two others injured.

The crash occurred around 8:22 p.m. east of Poka Street in Kahala, when the man, driving eastbound at a high speed, lost control of his vehicle and veered into the westbound lane, colliding with a parked car with two people inside, Honolulu police said.

Paramedics treated and transported the driver to a hospital in serious condition, while his 34-year-old female passenger was transported in critical condition, according to Emergency Medical Services.

The 28-year-old man in the parked vehicle suffered minor injuries and declined further treatment at the scene. His 26-year-old female passenger was taken to a hospital in serious condition.

Police said the 59-year-old driver was not wearing a seatbelt at the time of the crash, while his passenger was. Speed was cited as a contributing factor, but neither alcohol nor drugs were involved, police said.

The investigation is ongoing.