Two small planes collided in Colorado on Feb. 6, killing at least three people, authorities said.

The three dead came from both of the planes that crashed, Boulder County sheriff's office spokesman Rick Brough said. But there was no immediate information on how many people were flying in each of the planes.

Previous reports said two people were killed in the collision.

The accident involved a plane towing a glider and another aircraft, the Federal Aviation Administration (FAA) said.

One of the aircraft clipped the towline of the plane that was pulling the glider, FAA spokeswoman Laura Brown said.

The glider, described as a sailplane, apparently disconnected after the collision and landed safely a short time later.

Smoldering wreckage scattered in at least three areas on the prairie north of Boulder, which sits at the foothills of the Rocky Mountains.