Andrew Lloyd Webber narrowly avoided becoming embroiled in a massive police operation on Tuesday (23Apr13) when a young boy was stabbed outside a London school just hours after the famed composer paid a visit.

The theatre mogul was at Highbury Grove School in north London on Tuesday morning to launch a music scheme which provides instruments to deprived youngsters in a bid to prevent them joining gangs.

Lloyd Webber, who has donated $3.2 million (£2 million) to the project, spoke to students and posed for pictures during his time at the facility, but his visit was overshadowed by drama when a 15-year-old boy was brutally attacked outside the school just hours later.

The unnamed youngster, who is believed to be a pupil at the school, was stabbed on a bus and was airlifted to hospital where he remained in a critical condition as Wenn went to press.

Police officers swarmed the area and closed roads around the building during the drama. The boy was reportedly attacked as he was leaving school for the day.

Another 15-year-old boy, who has not been named, has been arrested on suspicion of attempted murder.