The year was 1972 and the crime was front-page news: a 65-year-old Columbia law professor on his way home was stabbed to death during a mugging. The Columbia Daily Spectator, a student newspaper, published a series of articles on the investigation. Mayor John V. Lindsay called for a citywide manhunt. One of those arrested was Daniel Mingues, a 16-year-old nearby resident, who eventually pleaded guilty to a lesser charge of robbery and was sentenced to up to seven years in prison.

Over the decades, as he was convicted of other crimes, including first-degree manslaughter, his name receded into memory at Columbia. But as though stepping out of the pages of local history, he appeared on campus July 1, students and the police said, carrying a digital copy of a 1972 article from The Spectator and demanding to know who had written it. According to a police spokeswoman, Mr. Mingues warned a university employee, “I’ve killed someone before and I can do it again.”

Starting out at Columbia’s Teachers College, where his mother was an employee for more than 30 years, he made his way to the building that houses The Spectator’s office, at Broadway and West 112th Street. The police say he got past the security system by following someone who swiped a secure identification card. The Spectator’s office was empty, but at the next door down the hall — a university development office — he held a smartphone on which he had called up the Spectator article, and he identified himself as its subject.

“He had a very aggressive, tense conversation with someone whose desk is visible from the doorway,” said a Columbia student who had been briefed on the incident, but who insisted on anonymity out of concern for his safety. According to the student, Mr. Mingues complained that the article failed to mention the real reason for the killing: because, he said, the professor was a neo-Nazi. (In fact, the professor, Wolfgang G. Friedmann, was a survivor of the Holocaust.)