Health chiefs are investigating the cause of a power failure which plunged Perth Royal Infirmary into darkness.
The outage happened at around 10pm on Saturday night, during one of the hospital’s busiest times.
Engineers were forced to use on-site generators to restore electricity throughout the facility, while emergency and GP services were temporarily diverted to Ninewells.
Power was fully restored after about 45 minutes, but engineers are still at the hospital trying to establish what went wrong.
Staff, who worked through the power cut and ensured there was no disruption to patients and services, have been praised for their professionalism.
A NHS Tayside spokeswoman said: “Following a temporary interruption to power supply at around 10pm last night, a team of engineers from NHS Tayside and specialists from SSE immediately attended and were able to reinstate the power using on-site generators.”
She said: “In line with our normal protocols, a temporary diversion to Ninewells for GP referrals and emergencies was put in place as a precaution, however the diversion was lifted a short time later. All services are running as normal and further engineering investigations are continuing.”
The spokeswoman added: “We would wish to thank all staff for their professionalism and continuing excellent work ensuring that there was no impact on, or disruption of services to, our patients during the brief period when power was interrupted.”