A 43-year-old Hawaii Kai man died in a single-vehicle crash after he struck a concrete pillar in Honolulu.

The Honolulu Medical Examiner’s Office identified him as Michael Kaneala Epstein. An autopsy is expected to be conducted Wednesday to determine the exact cause of death.

The crash occurred just before 5 a.m. today near Market City Shopping Center. Police said a 1996 Toyota Camry operated by the man was traveling east on South King Street and was making a left turn onto Kapiolani Boulevard when, for unknown reasons, the vehicle veered off the roadway and struck a concrete column.

Honolulu Fire Spokesman Capt. David Jenkins said an off-duty firefighter assisted the driver prior to the arrival of on-duty firefighters.

Two employees at Coffee Bean & Tea Leaf at the shopping center said they saw a man in a pickup truck pull over to help the injured man before Emergency Medical Services and firefighters arrived.

Paramedics transported the man to Queen’s Medical Center in critical condition where he later died. He was the sole occupant of the vehicle. EMS Spokeswoman Shayne Enright said the driver was not wearing a seatbelt at the time of the crash.

Police said speed was not involved. It’s unknown at this time whether alcohol or drugs were factors.

The investigation is ongoing.