Updated

A young gorilla kept at the San Francisco Zoo died Friday in what staff described as a "tragic accident.

Zoo spokeswoman Abigail Tuller told KTVU that staffers were carrying out their post-closing routine of moving animals into their night quarters when the gorilla, named Kabibe, unexpectedly darted under a closing hydraulic door.

Tuller said the death was particularly difficult for zoo staff who provided 24-hour postnatal car for Kabibe until she was 6 months old, and noted that this type of accident was extremely rare

Officials said the zoo was investigating how and why the accident happened, as well as whether changes in zoo policies, procedures and training are necessary.

Kabibe, whose name means "little lady" in Swahili, was born on July 17, 2013 to parents Nneka, 16, and Oscar Jonesy, 33, according to zoo officials. When she was 6 months old, zoo staff gradually introduced her to the gorilla troop, beginning with the family matriarch, Kabibe's grandmother, Bawang, 34.

Tuller said Bawang and Kabibe bonded instantly and had been inseparable ever since. Officials described Kabibe as a "beloved" member of the zoo family who brought "great joy" to the lives of the gorilla troop.

"Some animal deaths are more difficult to process than others, and this tragedy has struck us all in the deepest way imaginable," San Francisco Zoo executive director Tanya Peterson said in a statement.

Peterson urged the public to be patient as the gorilla family and zoo staff mourn the loss of the gorilla.

The zoo's gorilla preserve will remain open to the public, but officials said it may be closed periodically in the days ahead as the need arises.

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