UPDATE- The state fire investigator tells WZZM 13 News that the investigation into the cause of the fire could take a week.

Due to the extent of the damage over a large area and the cost of the damage, the investigation will take a while.

MONTCALM TOWNSHIP, Michigan (WZZM) - An early morning fire did millions of dollars worth of damage to Nelson's Speed Shop in Montcalm Township, the second time in 11 years the business has gone up in flames.

Ten units of firefighters arrived on the scene, which is just north of Greenville, about 1:30 am Friday. At times, witnesses say flames shot 40 to 50 feet in the air.

Firefighters say the blaze started in the back of the building, by the cold storage.

Nelson's sells motorcycles, jet skis and snowmobiles and employees about 25 - 30 people. Firefighters were able to save about 20 vehicles, but they estimate the damage to the building and equipment will be millions of dollars.

Owner Jack Nelson told WZZM 13 the building is a complete loss.

This is not the first time fire struck Nelson's Speed Shop. It was set on fire in September of 2001. At that point, the owners said they lost $2.5 million. In that fire, Richard Crew and Stewart Barron were charged with arson.

Nelson said he is not going to jump to any conclusions on what may have caused this fire.  The last one was set on the side of the building. Nelson said he hasn't even started thinking ahead yet to what he will do in terms of rebuilding or keeping the business.

There is no word yet on a cause of Friday's fire. The fire marshall is expected to start investigating this morning.

 M-91 is now open again in front of Nelson's.