Two top officials have been arrested at the Ryan International School in Gurgaon, where a seven-year-old boy was murdered in a toilet on Friday. The principal, Neerja Batra, was detained and questioned till after midnight yesterday. The arrests of the regional head and the Human Resource (HR) chief follow an investigation that has pointed at serious security lapses after a school bus conductor was arrested for the Class 2 student's murder after a sexual assault attempt. The school will stay shut for now except for students of Classes 6 to 12, who will sit for exams from Wednesday. A team of Haryana policemen are headed to Mumbai to question the school's management.