A woman barricaded herself and threatened staff at Luisen Hospital in the German city of Aachen on Monday.
When heavily armed police arrived, they shot and injured her "to put an end to the dangerous situation."
The 65-year-old woman had a gun and threatened employees of the physiotherapy practice, according to police.
She also set off pyrotechnics inside the hospital, German press say.
The site and the surrounding area were evacuated.
Almost 400 patients and staff were inside the hospital.
The incident took place at Luisenhospital in Aachen, a city which borders Belgium with around 252,000 residents.
"According to current information, a female (65) entered the hospital in the afternoon. Shortly afterwards, employees noticed smoke developing near the woman. The 65-year-old has now barricaded herself in a room. The surrounding rooms have been evacuated. Special forces are on site," Aachen Police said in a statement on Monday evening.
At around 11 p.m. local, police managed to remove the woman from the hospital, local media including Stern.de and Bild and the German news agency DPA reported.
This came several hours after emergency services were called to the scene.
