The only confirmed sighting I've heard of was Delaware County, PA and that one escaped or was let loose. Wreaked some havok, and I don't know the outcome.
The last good article I read debunked all cougar sightings from TN North.
We had a cougar sighting here confirmed through DNA from scat found at the spot of the sighting. State biologists thought it was either a runaway domestic animal (who the hell keeps cougars?) or an animal that was just "passing through" the area.