Twin sisters studying with a ministerial servant in a midwest congregation saw the movie "Amityville Horror" in the theater and were very frightened. They called Brother J. to come get them after the movie and Elder H. was called to pick them up. The plan was to bring them back to Brother J.'s house and both brothers would pray over them.
During the car ride, the rear car door flew open to the screaming of the twin sisters. Elder H. pulled the car over to shut the door and lock it. Again, a mile later, the door flew open. Arriving at Brother J.'s house, the twin sisters were invited to sit at the dining room table and read scripture. One of the sisters was handed a Bible and asked to turn to a passage. Upon lifting the bible, the sister excalimed: "It's hot!" and dropped the Bible. Smoke emitted from the NWT and the sister showed burn marks on her hands. Then, a daughter of Brother J. came out of her bedroom. A shoe picked itself off of the floor in the room and hit the daughter on the head. The other daughter was in the bathroom at this time, and the figure of a man jumped out of the shower and scared her senseless.
I heard this story from Elder H. as he told it as we sat around a campfire late at night. In my congregation, "demons" were frequently seen by many and these stories were told. Of course, the remedy was to shout out "Jehovah! Jehovah!" which would send the demon running scared.
When I left the Witnesses, the demons were blamed, and even presents that I sent to my family were considered to be "demonized" and would induce supernatural dreams. These items were burned by my family.