A suspect was arrested overnight in connection with a grass fire that spread across 300 acres in the Ham Lake and East Bethel areas on Monday, the Anoka County Sheriff's Office said today.

The suspect is a 40-year-old Columbus man, the sheriff's office says. He is believed to be a volunteer firefighter from the area.

Residents of about 10 Columbus homes returned to their residences Monday evening after they were forced to flee as fire engulfed the Carlos Avery Wildlife Refuge in the northern Anoka County community earlier in the day.

The fire spewed smoke that could be seen from as far away as Blaine and New Brighton, Anoka County dispatchers and Department of Natural Resources officials said.

No injuries were reported by the Forest Lake Fire Department, which said the only apparent damage from the fire was smoke damage. Most of the evacuees lived on or near Zodiac Street NE. Rumors of arson spread almost as rapidly the fire itself. Fires have blackened three other areas in the vicinity recently. A DNR spokesperson said arson had been discussed, but the department had drawn no conclusions.