BEMIDJI  (AP) — Authorities in Bemidji are asking residents to travel only for emergencies after a severe thunderstorm caused widespread damage and knocked out most phone service in the city.

The National Weather Service in Grand Forks says a severe storm passed through the northwestern Minnesota city shortly after 7 p.m. Monday. Meteorologist Pete Speicher says preliminary reports are sketchy, but says the storm caused "numerous and significant tree damage" and also knocked down many telephone lines.

Speicher says the Weather Service issued the travel advisory at the request of Beltrami County Emergency Management. Calls to the local police and sheriff's office did not go through Monday evening.

Speicher says the storm produced straight-line winds of 70 to 80 miles per hour. Other communities in its path included Grand Rapids and Itasca.

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