Teenager critically stabbed in Nottingham city center; police investigate, trams disrupted.

A teenager was critically injured after being stabbed in Nottingham city centre's High Street near Old Market Square around 4 AM today. Police have cordoned off Cheapside and are investigating the incident, which has disrupted tram services. Chief Inspector Iain Blackstock urged the public to come forward with any information. The victim is in critical condition at the hospital, and no arrests have been made yet.