Wilfredo Lee/AP Nikolas Cruz, the 19-year-old gunman in the high school shooting that killed at least 17 people on Wednesday, had reportedly done "enormous preparation" for the act. Cruz is believed to have been equipped with a gas mask and smoke grenades. He reportedly pulled the school's fire alarm in the hope of causing massive casualties. A lawmaker said the Florida high school gunman that killed at least 17 people on Wednesday had done "enormous preparation" for the act and was equipped with a gas mask and smoke grenades. Sen.