A seven-year-old girl was raped at her school in the port town of Vasco, resulting in huge protests in Panaji on Monday night.Police have detained the headmistress of the school on charges of negligence.The second grade student was sexually abused in the school toilet next to the office of the headmistress during recess yesterday, by an unidentified person, police said on Tuesday.The incident came to light after the minor complained of pain and was referred for medical examination.