Seven officers were called to deal with a disturbance at a Northampton hospital unit.
Police were called to St Andrew's Hospital's Marsh ward at just before 6pm yesterday (Sunday).
Eyewitnesses told the Chron that four officers arrived on the scene. They were then joined by a police dog handler and, briefly, by two armed officers. The latter two reportedly had riot shields and what are believed to have been tasers.
A spokeswoman for Northamptonshire Police said the force was alerted by the hospital after threats were made to staff.
Marsh is a low secure ward deals with teenage boys who exhibit challenging behaviour. Patients have been referred by the courts having been found mentally unfit to be tried.
It's understood that the person who made the threats was a patient.
The force said they were left in the hands of the hospital.