Penn Manor High School will be closed Friday to students, faculty and staff.

An early morning fire today in a clothes dryer filled the school with smoke. The fire caused no injuries but firefighters had to work to clear the smoke. More than a dozen rescue vehicles responded to the fire, and emergency workers used fans to help ventilate the building.

Classes were delayed three hours.

 "Due to the amount of smoke in the building, the district is working with a fire restoration company to perform cleanup work," Superintendent Michael Leichliter said in an automated telephone message sent to Penn Manor families tonight and posted on the district website.

"The full extent of the work will take a number of weeks, but we would like to conduct extensive work Friday, Saturday and Sunday," he said in the announcement.

"This will make it difficult to fully occupy a large portion of the high school in and around the wing of the building directly impacted by the fire.

"All other buildings will be operating on a normal schedule."

Leichliter said today that the fire started after a custodian had washed cleaning rags and then placed them into a dryer in the Family and Consumer Science area of the high school. It appeared the dryer malfunctioned as the drum stopped spinning but the heat stayed on, causing the rags to catch fire, he said.