Protesters are seen brandishing placards and Japanese flags in a demonstration outside the office of Unplugged Inc., the Japanese distributor of the Academy-award winning documentary The Cove, in Tokyo in April. (Koji Sasahara/Associated Press)Two movie theatres in Japan have cancelled screenings of the award-winning dolphin hunt documentary The Cove after protests outside the offices of the film's local distributor.

Cinemart theatres in Tokyo and Osaka have cancelled their planned theatrical releases of the film later this month, citing angry phone calls and threats of picketing outside the cinemas.

"It's unfortunate that a few extremists scared one of the Tokyo venues from showing The Cove, but I'm confident that the Japanese people will now be even more curious to know what these few people are trying so hard to hide," said director Louis Psihoyos in a statement.

"The extremists themselves are scared of the truth being known because what they are trying to hide cannot survive debate."

For several months, protesters have gathered outside the Tokyo office of Unplugged, the Japanese distributor of the U.S.-made film, and the home of Unplugged's president to decry its release.

In April, the U.S. air force base in Yokota — located west of Tokyo — cancelled its screening of the film in order to be "sensitive to local political and cultural concerns."

The film made its Japanese debut at the Tokyo International Film Festival last October.

The Cove, which nabbed an Oscar and dozens of documentary film honours around the globe, presents a graphic portrait of the secretive annual slaughter of dolphins in the Japanese town of Taiji.

Only a small fraction of the Japanese population eats dolphin and whale meat, which contain high levels of mercury. However, some consider it part of Japan's culinary tradition and are angry at what they consider an outsider's attack on Japanese culture.

According to Unplugged officials, talks are underway to show the film at other theatres.Diver Mandy-Rae Cruickshank swims with dolphins near a Japanese cove where the mammals are hunted and slaughtered in the environmental documentary The Cove. (Associated Press)

With files from The Associated Press