A zoo keeper who was mauled to death by a tiger had "no reason" to be in its enclosure, the animal park's owner said today.
Sarah McClay, 24, was attacked by a Sumatran tiger at South Lakes Wild Animal Park, in Dalton-in-Furness, Cumbria, yesterday afternoon.
She was taken by air ambulance to Royal Preston Hospital but died later from her injuries.
Cumbria Police said the tiger was locked in its enclosure following the attack and that members of the public were not at any risk during the incident.
Police and Barrow Borough Council are investigating the circumstances surrounding the incident.
David Gill, the owner and founder of South Lakes Wild Animal Park, said Ms McClay was very experienced in looking after big cats and he had no explanation as to why she had entered the enclosure.
He told BBC Radio 5 Live: "After investigation by the authorities here and the police, it does seem that she just basically failed to follow the correct procedures.
"For some unknown reason, an inexplicable reason, because there is no reason for why she did it, she opened the door and went into the tiger enclosure and straight into the tigers, and now we'll never know why."
Mr Gill said Ms McClay, who was from the Barrow area, had worked at the wildlife park for a number of years and was "very proficient" in her work with big cats.
He said that it was against strict safety protocols to walk into the tiger's cage, adding that the zoo had passed a major inspection on Monday, in which it was praised for its safety standards.
Mr Gill said: "An emergency call went out over the radio and we responded immediately. I was on the scene within 30 seconds.
"It was just unfortunate that everything happened so quick. It's so difficult to talk about because it was so upsetting.
"We moved all the public back of course. I think one member of the public did witness a part of the attack but I don't think there was anyone else who saw that."
The incident happened at about 4pm, when staff were working as normal and the park was open to the public.
Emphasising that at no point was there any threat to the public, Mr Gill added: "It just seems quite inexplicable. None of us have been able to come up with a really reasonable conclusion.
"All we know is that no one else was involved, there was nobody with her, and for some unknown reason she opened a door and walked straight into the tigers."
Mr Gill described Ms McClay as "a very passionate girl, very enthusiastic" who was "extremely good at delivering conservation talks. A very valued part of our team. A very bubbly character, a very happy girl."
He said that Ms McClay's death was the second tragedy for the park this month, after another employee was killed in a road accident.
He told the BBC there were no plans to have the tiger put down, which has been at the park for 10 years since it was a cub.
Mr Gill said: "He didn't make the mistake. He was just there. It's so difficult because we don't blame him for what has happened.
"It would be very much a tragedy for him. He's one of the rarest animals in the world, a Sumatran tiger, and it's something we don't want to do."
Following Ms McClay's death the staff felt they wanted the park to carry on, Mr Gill said.
"There was a huge consensus of opinion that we should carry on," he added.
"It's not the park's fault if you will. It's not going to do anybody any good if we closed."
Police said Ms McClay's family were "very shocked and distressed" and had requested privacy to grieve.
Visitors were asked to leave the wildlife park before it closed early following the incident. It is expected to reopen as normal today.