At the now- closed Causeway Safari Park in Ireland some years ago, two or three adult male chimps escaped and went on the rampage in the cafeteria. There is film footage somewhere of visitors trying to protect themselves with chairs etc. Fortunately the chimps were shot dead before anyone was seriously hurt.
An old pair escaped from Whipsnade zoo enclosure about a year ago. Again, the male had to be shot as he moved outside the zoo. The female was captured without trouble.
The attacks I have read about that took place in the USA seem mostly to have involved so-called 'pet' chimps which have suddenly become agressive to people.