An audience member at the Metropolitan Opera sprinkled a powdery substance — what the police said may have been the ashes of his mentor — into the orchestra pit during an intermission of a performance on Saturday, setting off a police investigation and the cancellation of the rest of that opera and a production that evening.

The police said at a news conference on Saturday night that they had identified the audience member, a man, through video surveillance footage and interviews with witnesses he spoke to before the afternoon performance of Rossini’s “Guillaume Tell.”

John J. Miller, the deputy police commissioner for intelligence and counterterrorism for the Police Department, provided few details about the man or his mentor other than to say the man was from outside of New York and that the police were trying to contact him. The man told other patrons he was there specifically to sprinkle the ashes during the performance, the police said. Mr. Miller said the act may have been a violation of the city’s health code but that there was no criminal intent.

The episode, which unfolded around 4:30 p.m. during the second intermission of the opera at Lincoln Center in Manhattan, prompted the company to cancel the rest of the show and Saturday night’s performance of “L’Italiana in Algeri.” The Met will reopen on Monday.