BREAKING NEWS: A boy believed to have climbed into a balloon resembling a flying saucer that floated helplessly thousands of metres above Colorado has been found safe and well.

Falcon Heene was found hiding in the attic, fearing he was in trouble with his parents, after releasing the balloon.

The bizarre scene played out live on television and prompted fears that the flying saucer-shaped balloon would crash with the young child inside. The balloon rotated slowly in the wind, tipping precariously at times.

Television pictures from the scene showed the balloon had landed in farmland, but there was no sign of the boy.

Photographs emerged that appear to show an object that had fallen from the balloon sparking fears the child had fallen out of the balloon.

Click here to watch the video.

Officers also searched the child's home and surrounding area for signs of him.

The balloon travelled for more than two hours.

"The bottom of (the balloon) is contained and hasn't been breached," Eloise Campanella of Larimer County Sheriff's Department told CNN shortly after the balloon landed.

"So at this point we are thinking he did not fall out of it. He has to be somewhere on the ground near his home."

National Guard helicopters were scrambled and were monitoring the balloon when it landed.

Aviation experts said the boy could have survived the flight, but he would have been cold and possibly disoriented at high altitudes.

Cathy Davis of the Larimer County Sheriff's Department told reporters the experimental balloon was owned by the boy's parents and tethered behind the family's home.

She said two sons were playing outside when the older boy saw the younger one go into a plywood compartment at the bottom of the balloon and fly away as it slipped its rope tethers.

Falcon's father, Richard Heene, is a 'science detective' and storm chaser according to his My Space site.

He hosts a documentary series and radio show investigating the mysteries of science, The Science Detectives.

Last year, his site entry says, he flew into Hurricane Wilma to take magnetic field measurements and this year rode a motorcycle into a mesocyclone.