No fewer than four people have been killed in a shooting at Mercy Hospital in Chicago on Monday.
The dead are two female members of staff, a police officer and the gunman.
According to a British Broadcasting Corporation’s report, the two women killed were a doctor and a pharmaceutical assistant, Mayor Rahm Emanuel confirmed.
A police spokesman said the gunman had died in an exchange of shots, but it is not clear if he took his own life.
A second officer avoided injury after a bullet fired in his direction became lodged in his gun, police say.
Officials say the gunman appeared to target a woman with whom he was in a relationship but they do not suggest a motive.
“Chicago lost a doctor, pharmaceutical assistant and a police officer, all going about their day, all doing what they love,” said Mr. Emanuel. “This tears at the soul of our city. It is the face and the consequence of evil.”
Police say it started with a row in the car park between people who knew each other.
The gunman first shot the woman he apparently knew and then headed inside the building, closely followed by several police officers.
More shots were fired, apparently at random.
Mercy Hospital was quickly evacuated during the incident as armed police descended on the scene.
The hospital later confirmed that police were able to secure the area, ensuring the safety of dozens of patients.
Other images from the scene showed people rushing outside the facility, including some staff in uniform.
Police confirmed that an officer named Samuel Jimenez had died in hospital of his injuries.