A Buffalo man was arrested early yesterday after he shouted threats and ran toward Howard Stern, the radio talk show host, as Mr. Stern was arriving at work in a limousine in midtown Manhattan, the police said.

The suspect, Samuel Callea, was waiting outside a garage ramp at 600 Madison Avenue, at 58th Street, just before 5:30 A.M. when Mr. Stern's car pulled in, said Officer Valerie St. Rose, a police spokeswoman.

The officer said that as the limousine rolled by him, Mr. Callea ran into the garage, shouting at Mr. Stern: "I'm going to kill you!"

Mr. Stern's chauffeur, who has not been identified, got out of the car and struggled with and subdued Mr. Callea before escorting him out of the garage, Officer St. Rose said.