TULSA — While dog-sitting for his mother earlier this month, Bryan Whalen discovered video recordings of his mother and two other people engaging in sex acts with three dogs, according to an affidavit filed Monday in Tulsa County.

Authorities have charged Diane Whalen, 54, and Donald Roy Seigfried, 55, with crimes against nature, a felony that includes bestiality, said Capt. John Bowman of the Tulsa County sheriff's office.

Seigfried was arrested and released Tuesday on $10,000 bail. Bowman said Whalen had not been arrested, but authorities were in contact with her lawyer.

Bryan Whalen was feeding and taking care of his mother's dogs when he stumbled on the tapes June 1 and then turned them over to the sheriff's office, according to the affidavit. Diane Whalen was in the hospital at the time, according to the document. She had complained of possible food poisoning, but the illness turned out to be appendicitis, which required surgery, the court record says.

Bryan Whalen said he and his girlfriend found the tapes in a storage case while he was looking for medications that his mother's doctor had requested, the affidavit says.

It appears as though Diane Whalen was attempting to sell the videos over the Internet, according to the affidavit.

Bryan Whalen turned in more than 200 pieces of evidence from the home. After subsequent searchers of the home, authorities found 193 CD-ROMs and DVDs, 67 VHS tapes, 12 cassette tapes, two floppy discs, two computer flash drives and one photo album showing the sex acts, according to the document. Bryan Whalen also turned in a tripod and video lighting equipment, and it appears the videos were shot at Diane Whalen's home, according to the affidavit.

The affidavit says Diane Whalen is shown on the tapes engaging in sexual acts with dogs.

The affidavit alleges Diane Whalen was selling the videos through e-mails and instant messages.

Two members of the Whalen family contacted Wednesday declined to comment for this story.