Police investigating the death of 24-year-old Sarah McClay at South Lakes Wild Animal Park at Dalton-in-Furness, Cumbria, have suggested her death may have been a result of "technical or human factors".
McClay succumbed to her injuries hours after she was attacked by a tiger in its enclosure on Friday at about 3:50pm, during feeding time for the zoo's big cats.
Detective superintendent Andrew Slattery, from Cumbria Police, said the line of investigation centred on "the management of dangerous animals," a BBC report suggests.
Initial reports by police officials indicate enclosures at the zoo's various compartments were connected by lockable doors.
Officials further said that though the animal park does have systems to ensure keepers and animals do not come in contact at any time, the system had "failed".
Slattery added that though there is no "criminal investigation" ongoing at the moment, the systems and protocols at the park are being examined.
Director of the zoo David Gill said keepers follow "strict protocol" and that they would never enter an animal's enclosure without taking permission.
"You do not have a hope if a tiger gets hold of you," Gill added.
McClay did not survive the attack even though she was immediately airlifted to Royal Preston Hospital.
"They were very traumatic injuries," a spokesman for North West Ambulance Service said according to the report.
Gill said that McClay was a very experienced zoo keeper, particularly for tigers, and he had no idea why she had entered the enclosure.
Despite the suggestions that his zoo's systems had failed, Gill told BBC Radio that the attack happened because McClay failed to follow the correct procedures.
"After investigation by the authorities here and the police, it does seem that she just basically failed to follow the correct procedures," he said, while asserting that the zoo had just undergone a major inspection and was praised for its safety standards.
The zoo remained open on Saturday for the public to visit.
Gill had also told the BBC that there were no plans and no reason for the tiger to be put down.
The tiger is a member of the Sumatran sub-species, one of the rarest animals in the world, and was brought in to the zoo 10 years ago when it was just a small cub.
"He didn't make the mistake. He was just there. It's so difficult because we don't blame him for what has happened," Gill said.