Police arrest a schoolgirl after three people are stabbed at Co-op Academy in Blackley, Manchester, on Tuesday morning. Emergency services are called to the school, and students are kept in their classrooms during a lockdown. Reports indicate pupils are told not to leave their rooms while police respond at the scene, with officers remaining at the school in Blackley as the incident is handled. Authorities later confirm that a girl is arrested in connection with the stabbing. The available accounts focus on the immediate emergency response, including the lockdown and the presence of police at the school, and do not provide further details about the injuries, the suspect’s age beyond being a schoolgirl, or any motive. No additional outcomes such as charges or court appearances are described in the provided reports.