Los túneles pueden contener gases tóxicos potencialmente mortales, zonas inundables, superficies inestables y espacios que dificultan cualquier operación de rescate.Se desconocen los motivos de porqué lo hacen.

There’s no threat to the public and officers have scoured the sewer system to make sure “nothing nefarious had been left behind,” a law enforcement source said.

Since May 5, at least three of the unexplained sewer incidents have been recorded in Brooklyn and Queens.