There may sometimes be a blurry line between news coverage and marketing, but officials at the Federal Communications Commission say Comcast Corp. crossed it last September when they telecast part of a "video news release" touting a product, Nelson's Rescue Sleep, without disclosing Nelson as the source.

The FCC's enforcement bureau fined Comcast, the nation's largest cable operator, $4,000 for airing part of the Nelson's video during a CN8 news show "without proper sponsorship identification."

Comcast, based in Philadelphia, said it would contest the agency's action. "We did not receive any consideration, benefit or payment" for airing the video, said spokewoman Sena Fitzmaurice.

The fine, made public Monday, came in response to a complaint by two advocacy groups, Free Press and the Center for Media and Democracy, which say that some broadcasters and cable companies routinely use such video releases without identifying them as public-relations material.

"Viewers have a right to know who is trying to persuade them so they can make up their own minds about what they are presented," Commissioner Jonathan Adelstein said in a statement praising the fine.

Diane Farsetta, of the Center for Media and Democracy, said that in two studies last year, the group found 140 instances in which 111 broadcast or cable stations used video releases.

Only two included what the group considered adequate disclosure: a continuous on-air label indicating a release's origins. Farsetta said one was a report about the contraceptive Seasonale aired in May 2006 by KYW-TV (Channel 3).

The FCC said that during a September 2006 consumer segment on Art Fennell Reports, CN8 gave no indication of the source of a video release that said, "If you are one of the estimated 70 million Americans who have trouble sleeping - Rescue Sleep may be what you're looking for."

Comcast said its appeal would focus on two arguments the FCC rejected: that as a cable operator, Comcast is exempt from the rules in question, and that they should not apply when video is aired without payment.

Fitzmaurice said the FCC action raised First Amendment concerns, because "the segments in question were chosen by journalists in the course of reporting."

Beyond the FCC fine, the watchdog groups' complaints appear to have had some effect. Fitzmaurice said CN8 adopted a new policy last November requiring disclosure - including a continuous on-air label - when consumer reports include material from video news releases.

Contact staff writer Jeff Gelles at jgelles@phillynews.com or 215-854-2776.