Oak Harbor firefighters got a lot of hands-on experience fighting fires this past week.

They burned down the late Dorothy Neil’s former house on Barrington Drive Saturday as a training session.

Chief Ray Merrill with the Oak Harbor Fire Department said firefighters started blazes inside the house and put them out about 20 times before finally letting the structure burn to the ground.

Then, in the early hours of Monday morning, they were summoned to three separate, genuine residential fires — one of which may have been arson, according to Merrill.

Merrill said firefighters received the first call at 3:50 a.m. about a fire at a Southwest Harrier Circle residence.

It was reported as a structure fire, but firefighters arrived at the scene to find two cars on fire in front of a triplex home.

It took only about 10 minutes to extinguish the fires, but Merrill said the newer Cadillac and 2008 Chevrolet Impala are likely total losses.

The blazes were definitely suspicious, Merrill said, and fire investigators are working with the Oak Harbor Police Department on a possible arson investigation.

The second fire was reported at 3:54 a.m. at the Whidbey Island Manor nursing home on Southwest Sixth Avenue.

A water flow alarm was activated when a fire in the attic dropped down onto a shelf in a storeroom, Merrill said.

The heat from the modest conflagration caused a can of Raid bug spray to explode, buckling the walls and pushing the storeroom door off of its hinges.

Merrill said the fire was in an area separate from the residents. Nobody was injured and nobody had to be evacuated as the fire was quickly extinguished.

The fire was accidental. It was caused by “combustibles placed too close to a heat source in the attic,” he said.

Then at 4:21 a.m., firefighters were called to a fire at a home on Southwest Putnam Drive.

Merrill said beauty bark beneath a porch may have been smoldering for a couple of days after it was accidentally ignited by smoking material.

The deck and its supporting timbers caught fire.

Fortunately, Merrill said, a neighbor was leaving his residence early to go to the airport and noticed the fire. He called 9-1-1 and extinguished the blaze with a garden hose before firefighters arrived.

The house escaped structural damage, Merrill said.