Three people died after two small planes collided mid-air Saturday over Boulder County, Colorado, authorities said. Neighbors called 911 just before 9 a.m. after seeing a Cessna 172 and Sonex Xenos crash into each other. “It looked like he had a problem, because planes don’t go straight down,” Sean Tufts told FOX31 Denver. “There was no fireball, nothing, it just crumpled.” One of the planes crashed into a field, the other into a tree near Vance Brand Airport in Longmont, Colorado, about 30 miles north of Denver. 2 KILLED IN MINOR AIRCRAFT IN IDAHO The crash involved a four-seat Cessna 172 and a Sonex Xenos, a light, aluminum, domestic aircraft that can seat two people. (The Associated Press) Two people were found dead in one wreckage and one person in the other, the Boulder County Sheriff’s Office said. The identities of the victims were not immediately released. The Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) are investigating. One plane crashed in a field and the other in a wooded area. (The Associated Press) CLICK HERE TO GET THE FOX NEWS APP While the NTSB confirmed the pilots had clear skies at the time of the crash, neither aircraft was equipped with a collision avoidance system or contacted air traffic control, the station said. The agency added that none of the aircraft were required to do so. The Associated Press contributed to this report.