Labour leader Ed Miliband has said the killing of teacher Ann Maguire was an "appalling act".
The killing of Anne Maguire was an appalling act. My thoughts are with her family, the school and those pupils who witnessed the attack
Although a shocking attack, this is a rare attack. There are few other occasions when a teacher was stabbed inside their school by a pupil.
A 15-year-old schoolboy is in police custody tonight, suspected of stabbing to death his teacher.