Two people broke into the conductor's booth on a southbound R train late Thursday night and announced over the public address system that they were members of ISIS and were hijacking the train, the New York Daily News is reporting.

The suspects, who police sources identified only as in their twenties, ran out of the train when it reached Union Square station. The train was then taken out of service as investigators looked for clues, including how they got into the booth.

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The stunt comes in the heels of a tough night for the city, after two police officers, in an unrelated event, were shot at a Bronx housing project.