A 32-year-old staffer at an out-patient medical facility affiliated with Columbia University was stabbed by a patient Wednesday morning, police said.

The suspect, a 25-year-old man from Brooklyn, had an appointment at ColumbiaDoctors Midtown, a facility on the third floor of a West 51st Street building, police said. But it all went wrong when he pulled a knife at about 10:30 a.m.

The victim, who was not identified, was taken to Cornell Medical Center with non life-threatening injuries.

By the time police got there, the suspect no longer had the knife, and investigators were able to recover it.

It was not immediately clear why he pulled a knife on the man.

The suspect was taken to Bellevue Medical Center for a psychiatric evaluation, police said.

By Monday afternoon

advertisement | advertise on newsday

Elyce Ponte, 55, a nurse from Allentown, Pennsylvania, was in the waiting room when the chaos erupted. She said the suspect appeared to "on a mission."

"We heard security say someone's throwing couches around, so I dove behind a couch," Ponte said. "I was never really scared. I knew security was going to be right on him."

A representative for Columbia University declined to comment.