South Florida zoo staffers and friends of a veteran keeper killed by a Malayan tiger met to mourn her death as investigators sought clues as to what led the animal to violently turn on his carer.
Palm Beach Zoo officials also said the zoo would remain closed over the weekend after the death of Stacey Konwiser, 38, who was killed by the 13-year-old tiger in an enclosure known as the night house yesterday.
Tigers sleep and are fed in the night house, which is not visible to the public, said zoo spokeswoman Naki Carter.
Konwiser's husband, Jeremy, also a Palm Beach Zoo keeper, read a note of support to staff, said Carter.
The zoo is trying to establish a memorial fund in Konwiser's honour.
"This is a very difficult situation for all zoo staff, the Konwiser family and her extended zoo family," said a statement from zoo officials.
The animal is one of only 250 such tigers known to exist.The tiger was tranquillised and authorities had to wait until the sedative took effect before they could come to Konwiser's aid, West Palm Beach police spokeswoman Lori Colombino said.
Carter said the zoo, which has four similar tigers, serves as a "breeding ground to make sure they don't become extinct".
The investigation into the keeper's death is being carried out by West Palm Beach police, Florida Fish and Wildlife officials and by federal authorities with the Occupational Safety and Health Administration.
The Animal Legal Defence Fund says the keeper's death was preventable and urged federal authorities to impose penalties against the zoo.
"As long as employees are allowed to work in dangerously close proximity to tigers, elephants and other dangerous animals, a significant risk of serious injury or death persists," the California-based group said.
Since 1990, according to the group, at least 24 deaths - and 265 injuries - were caused by "captive big cats" in the United States. "These attacks, and scenarios where an animal escapes, have also resulted in the deaths of over 128 big cats, many of whom were endangered species," the group said.
Konwiser's death was the first of "a human involved in an animal incident in the 60-year history of the Palm Beach Zoo & Conservation Society", officials said.
Carter, the zoo spokeswoman, said that on the afternoon of the attack, Konwiser was doing her daily chores. "This was not out of the norm. What occurred was out of the norm."