Tests on an automatic door which crushed a baby gorilla at the San Francisco Zoo show it is working properly.
The manual shut-off switch on the hydraulic door in the gorilla enclosure wasn't pressed in time to save the baby gorilla, the San Francisco Chronicle reports.
Friday night, as staff was carrying out its nightly post-closing routine of moving animals into their night quarters, 16-month-old "Kabibe" was crushed to death when she darted under the hydraulic door as it was closing, spokeswoman Abbigail Tuller said.
Zoo officials tested the instant-stop switch on Sunday and said it was working perfectly.
Kabibe was one of the youngest members of the Jones Family Gorilla Preserve at the zoo. She died Friday in what staff described as a "tragic accident," the spokeswoman said.
Zoo officials barred reporters from entering the grounds on Monday.
The death was particularly difficult for zoo staff who provided 24-hour postnatal car for Kabibe until she was 6 months old, Tuller said. This kind of accident is extremely rare, she said.
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 Jones Family Gorilla Preserve will remain open to the public, but officials said it may be closed periodically in the days ahead as the need arises.
Bay City News contributed to this report.