While audiences across America united to give "American Sniper" the biggest ever opening weekend for a movie in January, the Clint Eastwood film has some in Hollywood at odds.

The war drama, which grossed over $100 million over the weekend and received six Oscar nominations, is based on the life of Navy SEAL Chris Kyle who served four tours in Iraq and was called the most lethal sniper in U.S. military history.

While Kyle's actions earned him multiple commendations of valor for his service in the military, one Hollywood documentary-maker was not impressed.

"My uncle killed by sniper in WW2. We were taught snipers were cowards. Will shoot u in the back. Snipers aren't heroes. And invaders r worse," "Farenheit 9/11" creator Michael Moore tweeted Sunday.

Actor Rob Lowe fired back at Moore's comments.

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Moore later took to social media to walk back his original post, arguing his tweets were not about Chris Kyle or "American Sniper," but instead only about his uncle's death.

But Moore wasn't the only Hollywood type who seemed to snub the film. "The Interview" star Seth Rogen also took to Twitter to criticize "Sniper" for what he seemed to characterize as a pro-war stance. He compared the Bradley Cooper-starring movie to a scene in Quentin Tarantino's "Inglourious Basterds" where a German sniper "heroically" killed more than 200 Allied soldiers.

Eastwood's film also got support from what may seem an odd source, the Oscar-winning actress Jane Fonda, whose appeararonce in Western Maryland Friday drew protests from veterans for her Vietnam visit in the 1970s. Fonda tweeted her support for the movie.

"American Sniper" star Bradley Cooper told FOX News "it became quite a responsibility to tell the story" after Kyle was killed last year at a shooting range in Texas. He also said he hopes the film will provide insight into the lives of soldiers and their families. 

"It was a keyhole into that life," Cooper said. "One thing that we were able to do was explore this man's life and this woman's life and their children and their family and in doing so hopefully get just a nugget, a kernel of truth, that people who actually have gone through it and are going through it can relate to it and not feel alone."

Warner Bros., who distributed the movie, had no comment on the matter.

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