Amid reports of funnel cloud sighting, Nat. Weather investigators due in Berks county where school roof was ripped off building. — John Rawlins (@JRawlins6abc) July 10, 2015

HAMBURG, Pa. (WPVI) -- The National Weather Service confirms a tornado hit Berks County on Thursday evening, where a funnel cloud was spotted and an elementary school was destroyed.Investigators say the tornado was an EF-1 with maximum winds of at least 105 mph.Chopper 6 was over the Blue Mountain Elementary School to survey the damage Friday morning.Most of the roof was torn off the school, and pieces could be seen on the ground.A portion of the roof was pushed up vertically, with a corner pointing into the sky.The video clearly showed the inside of classrooms, hallways and the gymnasium.Debris was scattered throughout the building and a wall was missing from part of the school.Action News obtained video of a funnel cloud that was spotted nearby.The school's principal, Rachel Wardecke, was inside the building finishing last minute chores before a planned vacation.She says there was little warning a tornado was about to hit.Fortunately, she was able to dig herself out of the ruins."I heard hard rain...then I heard the wind and I thought, 'Oh, wow!' When the ceiling tiles started flying at me that's when I knew it was more than a strong wind," said Wardecke.Principal Wardecke escaped with just bumps and bruises."Her guardian angel was working overtime. If you go in there and see the rubble, you'll know that he truly worked overtime for Rachel Wardecke and I thank God for that," said Richard Bianco, school official.Staffers and volunteers went through and collected books and other items that could be reused. They plan to hold classes, which are scheduled to begin in August, at a nearby sister school.Teacher Linda Johnson saved some curtains, vowing to use them in the future."When we rebuild, they will be in my new room - they will be proof that we have survived," said Johnson.Her husband is an Army veteran who volunteers here part of a team that affixed the stars and stripes to the schools storm damaged flag pole.Despite no one being hurt he says there had been shock and tears over what occurred."I just felt we need we needed something like a tissue to wipe the tears and I felt the American Flag was that," said Craig Johnson.There were no reports of any injuries during the storm.