An after-dark burglary and suspicious fire have left an office complex in downtown North Branch, Minn., seriously damaged, and police are looking for whoever is responsible.

The break-in and fire occurred sometime Tuesday night at the Main Street Center, a two-level building along the town's main east-west thoroughfare that has about 15 tenants, said property co-owner Deb Heggerston.

While a dollar value has yet to be placed on damage caused by the fire and water from the sprinkler system, Heggerston said the below-ground level of the 13,000-square-foot building is "pretty much trashed."

No one was in the building at the time the sprinklers went off, which was about 11 p.m., she said.

Heggerston said a nonprofit organization had a large television stolen, and small amounts of cash were pinched, as well.

She suspects that because "there wasn't so much money, they torched it" by igniting diesel fuel in the lower level.

Tenants include a realty, a massage provider and a hair dresser. Two new tenants were about to arrive, but "now I have to turn them away," Heggerston added.

Police say a reward of up to $2,500 is being offered for information leading to whoever is responsible for the crime. The state fire marshal's office is also investigating. Anyone with information about the case is urged to call police at 651-674-8848.

Paul Walsh • 612-673-4482