TUCSON, Ariz. - At the request of Comcast, the FBI has stepped in to investigate how roughly 30 seconds of porn interrupted the company's Feb. 1 Super Bowl broadcast.

Subscribers to Comcast's standard-def service in the Tucson area got an unscheduled glimpse of porn actors Evan Stone and Tristan Kingsley during the fourth quarter of the NFL championship. The scene came from Fusxion's Wild Cherries 5, which was running on the Club Jenna-affiliated Shorteez pay-per-view channel from Spice Entertainment.

Comcast has characterized the incident as a malicious prank. Spokeswoman Kelle Maslyn told the Arizona Daily Star the Philadelphia-based company has shared information with the FBI and will continue to cooperate fully with the investigation.

As previously reported by AVN Online, the Super Bowl broadcast was actually interrupted twice by material from adult PPV services. Comcast's internal investigation found that its own technical systems were working properly at the time.