A man was taken to hospital following an alleged slashing at a multi-storey in Dundee.
Police and an ambulance crew attended the incident at Lansdowne Court.
It is understood that a man was allegedly slashed with a razor blade.
Residents said about 10 police cars — including a riot van — descended on the area from around 8.30am.
Police Scotland confirmed that a man has been arrested in connection with the the incident. Inquiries are still at an early stage.
Eyewitnesses reported seeing CID officers at both Lansdowne Court and neighbouring Pitalpin Court.
Pitalpin Court resident Arthur Gaull, 65, a retired interior designer, said: “It all started around 8.30am when the police cars arrived with their blue flashing lights on — another four vehicles, including a van, came after that.
“By 9.15am, there were at least seven police cars at the scene. Then the ambulance came.
“There was a blue van here too and forensic officers got out of it.”
Another resident said that police were spotted on the second floor of Pitalpin Court before an arrest was made.
A man was treated for his injuries at the scene by paramedics before being taken to Ninewells Hospital.
A witness said: “There was a man on the ground. He was being seen to by paramedics, and was taken away in an ambulance.”
A spokesman for Scottish Ambulance Service confirmed a crew had been dispatched to the scene.
He said: “We received a call at 9.14am today to attend an incident at Lansdowne Court.
“We dispatched one ambulance to the scene and one male patient was transported to Ninewells.”
A spokeswoman for the police force said: “Police Scotland attended at Pitalpin Court and Lansdowne Court this morning after a disturbance.
“A man has been arrested.
“There is currently a police presence in the area and inquiries are at an early stage.”