Police said the victim was running near Longleat Drive and Westgate Drive when she was assaulted from behind around 5:15 p.m.
The attacker grabbed her arm and struck her in the face but he fled when the jogger fought back, township police said. He was last seen running toward Upper State Road.
A police dog team scouted the scene but turned up no sign of the assailant, according to the department.
He's described as a white man around 20 years old with a thin build, standing about 6 feet tall. He was wearing a black hoodie with the hood pulled closely around his face, investigators noted.
Anyone with information is asked to call Montgomery Township Police Department's Detective Division at 215-362-2301 or email police@montpd.org.
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