The media and entertainment industry's biggest giants are partnering to create their own Internet video-distribution network, aimed squarely at Google Inc.'s popular video site, YouTube.

NBC Universal will join Rupert Murdoch's News Corporation Inc. to provide content -- such as Fox's "24" and NBC's "Heroes" -- for distribution beginning this summer on AOL, Yahoo, Microsoft Corp.'s MSN and News Corp.'s MySpace sites, the companies said today.

Also included in the new free, ad-supported service will be movies from Universal Pictures and News Corp.'s 20th Century Fox studios, such as "Borat" and "Little Miss Sunshine."

"This is a game-changer for Internet video," said News Corp. President Peter Chernin. "We'll have access to just about the entire U.S. Internet audience at launch. And for the first time, consumers will get what they want -- professionally produced video delivered on the sites where they live."

The companies said their Internet partners -- AOL, MSN, Yahoo and MySpace -- cover 96 percent of monthly unique users on the Internet.

Even before Google bought YouTube for $1.65 billion in October, the video site was under attack from content-providers, such as Viacom Inc., home of MTV, Nickelodeon and Comedy Central. Viacom and other companies said YouTube, which is free and ad-supported, posts copyrighted material -- such as clips from Comedy Central's "The Daily Show" -- without receiving authorization from Viacom.

And even though YouTube is filled with amateur video -- anyone can shoot a video and upload it to the site for free -- the most popular videos on the site come from companies such as Viacom, the company said, driving viewers and pumping up YouTube's ad revenue.

The fight between Viacom and YouTube escalated last week, when the entertainment company filed a $1 billion suit against Google and asked a judge to issue an injunction against YouTube to prevent it from posting more unauthorized video.

Google says YouTube complies with copyright law and removes unauthorized videos when they are discovered. Viacom calls YouTube's efforts at policing half-hearted.

The new video site from NBC and News Corp. will allow users to search videos, create playlists, join communities and make mash-ups -- user-created combinations of several videos.