A woman told police she was woken up by her growling dog.
That's when she saw the intruder, in her bedroom, naked.
She screamed, and the man ran away.
Tuesday night, police walked up and down the street, alerting neighbors of the break-in on their normally quiet block.
"I'm really sorry to hear this, if it happened, and I hope they find out who it is," said Paoli resident Patricia Uberti.
The woman, in her 30's, lives alone. It's not clear if she was targeted or if the suspect knew her, but she tells police she did not recognize the man in the few moments he stood in her bedroom.
Police are taking this case very seriously.
"This is a high level of desperation for a criminal to do something like this," said Capt. Andy Chambers of the Tredyffrin Twp. Police. "Therefore there's a high level of danger."
Police reminded people to lock their doors and windows and take common safety precautions.
It appears the suspect broke into the woman's home through an area that was under construction.
Investigators believe he might have disrobed in the kitchen before going into her bedroom.
The suspect is described as a white male, 6 feet tall, stocky build, with light brown shoulder length hair.
He was last seen running through backyards toward Biddle Road, one street away from the scene of the break-in.
Police say nothing was stolen from the home, and the woman is crediting her 100 pound rottweiler with potentially saving her life.
The dog woke her up and she was able to put her glasses on just a few seconds before the intruder showed up.
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