BOSTON (AP) — A giraffe that starred in a series of TV commercials for Toys R Us and appeared in Jim Carrey's movie "Ace Ventura: Pet Detective" has died at a Boston zoo.

American Humane, an animal welfare group that oversees animal treatment on movie sets, said Tweet the giraffe died Friday at the Franklin Park Zoo where producers are filming the Kevin James movie "The Zookeeper."

The 18-year-old giraffe didn't belong to the zoo and had no known health problems.

Tweet collapsed in its enclosure while feeding and in the care of his trainer. Results of a necropsy are pending.

The animal welfare group, People for the Ethical Treatment of Animals, alleges Tweet was mistreated and has asked for an investigation. American Humane denies mistreatment.

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