HONOLULU » Honolulu police are warning they plan to set up checkpoints during the next two months to search for people driving under the influence.

The checkpoints will be set at unannounced times starting Friday through April 30 — a span that includes St. Patrick’s Day, spring break and the Easter holidays.

The Honolulu Police Department said Monday nine people have been killed in eight traffic collisions on Oahu so far this year. Speed, alcohol or drugs were a factor in six of the crashes.

The police say they’ve been setting up impaired driving checkpoints every week since October as part of the federal "52/12" sobriety checkpoint program.