A 45-year-old Honolulu police officer was seriously injured when his motorcycle crashed on the H-1 Freeway yesterday.

The accident occurred shortly before 4 p.m. in the eastbound lanes near the Middle Street off-ramp. Police said the officer was responding to a call and his blue lights were flashing when a white truck cut in front of him.

The officer swerved to his right to avoid the vehicle and hit a barrier while going about 30 mph. The officer was thrown from his motorcycle and apparently lost consciousness, according to Emergency Medical Services personnel.

EMS said the officer was conscious when he was taken to The Queen's Medical Center.

The officer was wearing his helmet at the time of the crash. He was in serious but stable condition at Queen's, and undergoing tests last night.

Capt. Frank Fujii, police spokesman, did not disclose the officer's name, but did say he is a five-year veteran of the force.

Yesterday's accident was the second this year in which a motorcycle officer was seriously injured in a crash. On Feb. 10, an officer was injured after he lost control of his bike and crashed on the Pali Highway.

Reach Curtis Lum at culum@honoluluadvertiser.com.