Emergency 911 phone service went down for almost five hours in all or part of several Minnesota counties Saturday, and representatives of CenturyLink said they were unsure what caused the problem.

Benton, Sherburne, Stearns and Wright counties and the western portion of Hennepin County were affected by the outage. Callers in those areas could still report emergencies by using the main phone numbers for the sheriffs' offices.

CenturyLink spokeswoman Joanne Hjelmeland said the outage lasted from about 11:30 a.m. to about 4 p.m. "It can take awhile to investigate," she said.

The problem only affected calls made from landline phones. Stearns County Sheriff's Office Sgt. Robert Schwegel said they learned of the outage about 12:15 p.m. when they received calls from people who called the office number to say they had gotten busy signals when trying to call 911.

Schwegel said the 911 service was restored about an hour later for callers within St. Cloud city limits.

Schwegel said his office contacted CenturyLink and also contacted other neighboring counties, telling them they should check their 911 service. A spokesman for the Benton County Sheriff's Office said they learned of the problem after getting the call from Stearns County.

Susan Feyder • 952-746-3282