A cargo airplane crashed while attempting to land overnight in the northern Mexican city of Monterrey, killing all five crew members, authorities said Wednesday. Rescue workers were trying to determine if a sixth person was killed inside a car that may have been crushed under the airplane, a Mexican transportation official told Televisa television. The Airbus A300 was trying to land in rainy and cloudy conditions late Tuesday when it crashed on a road leading to the international airport of Mexico's third-biggest city, Nuevo Leon state officials said. The airplane, belonging to Mexico City-based Aerotransporte de Carga Union, had taken off from Mexico City. Authorities were investigating the cause of the accident.