The perpetrators of November’s terrorist attacks in Paris used burner phones, according to details that emerged over the weekend, calling into question how extensive their use of encryption may have been. The details contradict earlier reports leaked by officials who were supposedly familiar with the investigation.

“The three teams in Paris were comparatively disciplined,” according to a 55-page report compiled by French authorities and reported by The New York Times over the weekend. “They used only new phones that they would then discard, including several activated minutes before the attacks, or phones seized from their victims.”