Two opera performances in New York had to be cancelled yesterday after an audience member sprinkled an 'unidentified powdered substance' into the orchestra pit - with witnesses suggesting the substance was human ashes.
The incident happened at the The Metropolitan Opera in the city's Lincoln Center.
According to the opera company, the performance of Guillaume Tell (William Tell) had to be cancelled during the second intermission.
A later show - L’Italiana in Algeri - was also called off as investigations continued.
Technical teams have examined the substance, with health officials due to carry out more extensive tests.
The NYPD's Deputy Commissioner of Intelligence & Counter-terrorism, John Miller, told reporters: “We have spoken to more than one witness who said they spoke to an individual from out of town, who indicated that he was here to sprinkle ashes of a friend - his mentor in opera - during the performance. That is certainly an area we are pursuing."
The suspect is believed to have fled the scene, with Mr Miller adding that "we have gotten a very good description of an individual who was seen sprinkling this powder".
Deputy Commissioner of Intelligence & @NYPDCT John Miller speaking on incident at Lincoln Center tonight. pic.twitter.com/3yKPYEYFz2
— NYPD NEWS (@NYPDnews) October 30, 2016