An expensive piece of logging equipment caught fire north of Duluth, and authorities suspect arson is behind the blaze.

The blaze was reported to the St. Louis County Sheriff's Office about 12:45 p.m. Saturday about 25 miles north of Duluth along N. Alden Lake Road in Gnesen Township.

Fire crews extinguished the blaze but not before the Caterpillar 521B Feller buncher was considered a total loss.

The Sheriff's Office said the equipment, a harvester with a crane-like arm that grabs and takes down trees, was worth more than $500,000. It was owned and operated by Doug Hustad Logging, based in the Gilbert area on the Iron Range.

Logging activity was idle at the time of the fire, "and the fire is being investigated as a possible arson," a Sheriff's Office statement read.

Anyone in the area around the time of the fire is urged to call the Sheriff's Office at 1-218-336-4350.

Paul Walsh • 612-673-4482