The blaze broke out at 2:30 a.m. Thursday at East Main Street and Route 100 in Macungie.
Flames were showing from the rear of the building when firefighters arrived at the Boyko Funeral Home.
Crews quickly sounded a second alarm as they worked to contain the blaze and keep it from spreading to nearby homes.
Action News is told the rear part of the building houses residential apartments.
The fire was declared under control by 5:45 a.m. There were no immediate reports of injuries.
Macungie funeral home fire now under control after stubborn flames on 3rd flr where fire may have started. No inj. pic.twitter.com/HHPwEb0kCs— Jeannette Reyes (@6abcJeannette) April 20, 2017
Fire officials suspect the blaze started in a residence in the rear third floor part of building.
Investigators are working to determine what touched off the fire.
Route 100 was closed in both directions at the scene as firefighters worked to contain the situation and hose down hot spots.
Stay with Action News and 6abc.com for more information as it becomes available.
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