A killer tiger could have caused "multiple fatalities" at a zoo after gates to a public area were left open for up to 80 minutes, a report has found.
Keeper Rosa King, 33, was mauled to death by eight-year-old Malayan tiger Cicip as she cleaned his enclosure at Hamerton Zoo in Cambridgeshire.
Before her death she had opened two gates - meaning the tiger had access to visiting families and children for a lengthy period of time.
The enclosure was only secured after a member of the public spotted Rosa's bloodied body.
Assistant Coroner Nicholas Moss said it was "largely by chance" that members of the public including young children were not killed.
He has written a Prevention of Future Deaths report calling for Defra and the HSE to provide clearer guidance on "airlock" gates for zoos.
Assistant Coroner Moss said: "There was a serious risk of casualties and fatalities to the visiting public.
"The metal gate and wooden gate were both open.
"For a period of no less than 15 minutes and possibly as long as one hour and 20 minutes, Cicip could simply have walked out of the tiger enclosure into the public areas where families with children had already been admitted.
"It was thus largely by chance... that the risk of multiple casualties/fatalities to the public did not in fact materialise.
"Members of the public including children had congregated by the open wooden gate.
"They could easily have been killed."
He added: "I am concerned that a simple human error on the part of a safety-conscious experienced zoo keeper led to a situation whereby a tiger could have attacked multiple members of the visiting public."
Rosa, who had 13 years experience as a keeper, suffered fatal neck injuries when she was attacked at Hamerton Zoo, Cambs., in May 2017.
In July an inquest heard she had probably failed to check Cicip was secured in his den before entering the tiger enclosure.
Before her death she opened a wooden and metal gate to gain access to the area.
While Rosa lay dead visitors to the zoo were completely unaware that Cicip could have walked free at any time.
Defra's 'Standards of Modern Zoo Practice' states that "in general" double door systems should be in place at zoos.
The Health and Safety Executive's 'Managing Health and Safety in Zoos' adds that "normally" two gates should be provided to stop animals escaping.
In his report Mr Moss has revealed he is "concerned" about the wording of the guidance.
Calling for the two bodies to "take action" he added: "I heard evidence from both Hamerton zoo and the independent expert in zoo management and design that not all other zoos had airlock type double keeper gates even for tiger enclosures.
"The Defra guidance by inclusion of the words "in general" is insufficiently clear and insufficiently prescriptive on the standards that should apply to an enclosure holding animals as deadly as Tigers.
"Similar considerations apply to the HSE guidance "The fact that other zoos may not have double keeper gates fitted to tiger enclosures and the lack of more prescriptive guidance carry a risk of further deaths."
The report says that Hamerton has since fitted airlock gates to entrances at the tiger enclosure.
But Mr Moss also said he is worried to hear the zoo has no firearms on site to deal with any future escapes.
He wrote: "I am concerned that more than two years after Rosa's death, the process of the zoo obtaining conventional firearms has still not been completed. This carries a risk of further deaths".
Mr Moss send his report, which was written in July, to Hamerton Zoo,
Cambridgeshire police the HSE and Local Government Association.
A spokesman for Hamerton yesterday (Thurs) told the Mirror they had been "asked not to comment" on the report.
Defra and the HSE have been approached for comment.
