About 200 Hawaiian Telcom customers across the islands experienced problems with their “voice-over-IP” phone service for about three hours or more Tuesday.

About 150 of the 200 phone customers were businesses that saw phone service disrupted from about 9:45 a.m. to 12:30 p.m., although some customers could have seen a further delay before service was restored, Hawaiian Telcom spokeswoman Ann Nishida Fry said.

The Honolulu Star-Advertiser was among those customers whose phone service was down from about 9:45 a.m. to 2:45 p.m.

The problem was traced to a call-processing switch that also caused disruptions for some residential customers whose calls went through the same switch, Nishida Fry said.