A 76-year-old man wielding a knife attempted to commit suicide outside the set of NBC's morning programme, the Today Show.
Police say Pak Chong-Mar was taken into custody after he slit his wrists in New York City's Rockefeller Plaza while yelling that the government was trying to take his house. He also indicated he was upset with the IRS.
The man's injuries were not life-threatening, and he was taken to hospital for a mental health evaluation.
Today Show host Matt Lauer said later in the broadcast that medical personnel had responded to an outdoor area where spectators gather to watch the programme's recording.
"He was controlled by our security team out there. However, he did harm himself in some way, so he's now being attended to by medical personnel," Lauer said.
He added: "He did manage to cut himself."
Nobody else was hurt in the incident, though several bystanders were treated for exposure to blood.
New York police and NBC security cleared the area and are investigating the situation. The incident was not believed to have been captured by TV cameras.
Lauer also tweeted: "All secure on the plaza after a scary incident. Thanks to our security team and the NYPD."