NEW YORK (CBSNewYork/AP) — An animal welfare group says an elephant named Happy who has lived alone since her mate was fatally injured is being “unlawfully imprisoned” by a New York City zoo.

In a legal petition filed Tuesday in Orleans County, the Nonhuman Rights Project says Happy has similar rights to a human being and should be relocated from the Bronx Zoo to a larger private sanctuary.

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Bronx Zoo Director Jim Breheny says the lawsuit is based on “ludicrous legal arguments and lies.”

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Happy was paired with another elephant named Grumpy for 25 years. Grumpy died in 2002 after he was injured during a confrontation with two other elephants. She was then paired with Sammy, who died in 2006.

Zoo officials say Happy is content, not isolated and might suffer from a transfer.

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