Mayumi Heene, the mother of "balloon boy" Falcon Heene, admits that she and her husband lied to police about their son floating off into the skies in a homemade balloon. Last Saturday, she told a sheriff's investigator that she and her husband Richard knew all along that the 6-year-old boy was hiding in the family's Colorado home while police and rescuers chased it, believing the boy was trapped inside.

All this was revealed in a search warrant affidavit released Friday, which also reveals that the parents planned the hoax for about two weeks and that the balloon was constructed for the stunt.

Investigator Robert Hefferman said:

"The motive for the fabricated story was to make the Heene family more marketable for future media interest. She and Richard had instructed their three children to lie to authorities as well as the media regarding the hoax."

On October 15, the balloon drama dominated TV as the networks followed the progression of the drifting balloon as it floated thousands miles into the air before landing three hours later over a hundred miles from the family's home in Fort Collins.

Falcon was found hiding in a cardboard box inside the family's attic above the garage. The family's story began to unravel during an appearance on CNN. During the appearance, Richard asked his son why he didn't come out of the attic when his name was called.

The boy replied:

"You guys said that, hmm, we did this for the show."

Richard Heene explained that he had "no idea" why his son would say that, and denied it was a trick.

Police are planning to charge the parents with conspiracy, contributing to the deliquency of a minor and attempting to influence a public servant. They're also being charged with a misdemeanor charge of filing a false police report. The charges haven't yet been made though.

Authorities will also seek the reimbursement of the cost of the rescue, which may run into the hundreds of thousands of dollars.