A member of staff at a hospital has been injured in a stabbing, which has resulted in the site being locked down.
The 56-year-old man was attacked at Royal Sussex County Hospital in Brighton, at about 08:40 BST.
His injuries are not life-threatening and he is “stable and safe”, the hospital trust said. Armed police remain at the scene.
A 30-year-old man was arrested on suspicion of attempted murder in nearby Wilson Avenue at about 09:40.
In a statement on Twitter, the Brighton and Sussex University Hospitals NHS Trust said the victim was being cared for in the hospital.
It said members of the public were not being allowed on site as it was still being searched.
Sussex Police said the “apparently isolated and unexplained incident” was not being treated as terrorism at this stage.
It said officers worked quickly with hospital security staff to ensure nobody else was injured and “staff and patients were safe”.
“There is currently nothing to suggest that any other person has been involved or that anyone else is at risk,” it added.
Sussex Police and Crime Commissioner Katy Bourne called it a “dreadful event” and said her thoughts were with “the injured NHS staff member’s family and those police officers and health colleagues at the scene”.
Kemptown MP Lloyd Russell-Moyle told the BBC his thoughts were with the worker and his family.
He added: “Last year Labour passed (through a back bench Bill) a law to ensure that people who assault NHS workers got double time.
“This will be no relief to the person who was stabbed but I hope it will ensure justice can be delivered when the person is brought to book.”
Hove and Portslade MP Peter Kyle tweeted that it was “shocking news” but thanked police for a “swift arrest” and wished the staff member a “speedy recovery”.