I have heard alot of stories about happend ghosts and spirits. and something happend in the college i studied my intermediate. The hosteler girls played a spirit game and some thing happend and all the girls are became very scare then they called church father to pray god and they wrote few slogans of god on their room doors "jesus and om sai ram, ram, jai hanuman
They must have had a plan chit where they must have called the spirits, however,it is generally manipulated by someone or the other individual present there and the atmosphere created also helps the illusion ..