A fire that destroyed a mobile home last month in Big Lake has been ruled a case of arson, authorities said.

An officer on routine patrol in the Big Lake Estates Mobile Home Court noticed a suspicious vehicle around 4 a.m. on April 20 in the 300 block of Monroe Street. About 20 minutes later, a mobile home caught fire in the same area where officer Joe Kalla had seen the driver of a car acting suspiciously.

Kalla arrived to find the home engulfed in flames. He made sure the home was unoccupied and evacuated residents of nearby units before the Big Lake Fire Department arrived and put out the blaze.

The state fire marshal's office and Big Lake Police are calling the fire arson. The homeowner was out of town and is not a suspect in the investigation, authorities said.

Authorities are asking the public for help finding the person responsible. Anybody with information can call Big Lake Police at 763-251-2987.

Tim Harlow