Two people have been stabbed at a hospital, with one man critically injured.

A man was arrested outside Central Middlesex Hospital in north-west London with life-threatening injuries which are believed to be self-inflicted, the Metropolitan Police said.

Armed police were called to the scene at 1.18pm on Wednesday and the hospital was locked down temporarily.

Officers found two people with stab injuries.

The first person has injuries that are being treated as life-threatening but the second victim’s injuries are not.

The force said the incident is not being treated as terror-related.

A spokesman for the Metropolitan Police said: “Officers will remain in the hospital as further searches are conducted but at this time they are satisfied that no one else is sought.

“Police are working to establish the circumstances. At this time the incident is not being treated as terror-related.

“The hospital was temporarily locked down but has now reopened and will be operating services as normal. There is a heightened police presence at the hospital while we investigate.”

Amie Ferris-Rotman, who was visiting the hospital dialysis unit with her father, told Sky News that police checked the area where they were before locking them in a nurses’ room for about 45 minutes.

She said: “All the dialysis patients were quite freaked out.

“And at one point those who were about to go on to dialysis were put on wheelchairs and brought into a room, which is where we were as well, and they were locked in.”

The trust which runs the hospital said it has reopened and services will “continue as normal”.

A spokesman for London North West University Healthcare NHS Trust said: “We can confirm an incident took place at Central Middlesex Hospital this afternoon.

“Police are on site and the hospital was temporarily locked down for a short period of time as a precautionary measure.

“Working closely with the Metropolitan Police, we have now reopened the hospital and services will continue as normal.”