Zookeepers at the Honolulu Zoo are scratching their heads over how one of their tigers — an 8-year-old Sumatran male named Berani — managed to slink out of his enclosure Thursday morning, KITV.com reported on its Web site.

Zoo officials believe Berani escaped after an employee accidentally left open one of the doors to the tiger exhibit, according to the ABC affiliate.

Berani reportedly wandered out of his enclosure around 8:15 a.m. Zookeepers responded quickly in turning the tiger back before anyone could be injured, KITV.com reported.

According to the Honolulu Zoo's Web site, Sumatran tigers are the smallest of the tiger subspecies. Males like Berani average eight feet in length and weigh around 265 pounds.

Zoo officials told KITV that Berani, who was raised by humans, is the gentlest of the zoo's three Sumatran tigers. They believe he may have left his enclosure in search of his partner, another tiger named Chrissie, KITV.com reported.

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