Two American pilots whose executive jet collided with a larger passenger jet over the Brazilian jungle, killing 154 people, said Friday they were flying at the altitude assigned by air traffic controllers. Speaking publicly for the first time about the September 29 crash over the Amazon region, Joseph Lepore and Jan Paladino told NBC News that they never saw the larger airliner and could not avoid the collision. Paladino said they were flying at 37,000 feet, as directed, and could not have left that altitude without permission. Air traffic controllers have responsibility to manage that traffic, he said. Flight controllers have been under investigation in the crash, and Brazil federal police superintendent Daniel Lorenz Azevedo said Wednesday that other people may be charged. The collision killed everyone on board the Gol Airlines Boeing 737 in Brazil s worst air disaster. The smaller jet landed safely with all seven people aboard unharmed. Brazilian authorities have formally accused the two American pilots, saying their lack of caution played a role in the crash. In a preliminary report, police said the pilots could have prevented the disaster if they had noticed their airplane s transponder was turned off. A Brazilian judge will decide whether to indict the pilots and send them to trial. If convicted, each could face up to 12 years in prison.