London Zoo has been criticised by inspectors after failing to report the escape of a venomous viper snake.
The Sri Lankan green pit viper slithered out of a vivarium in the reptile quarantine building but was soon recaptured by a keeper that saw it through a window.
A 2013 inspection report said the August 2012 incident was not reported to the Camden council, suggesting there was a "serious breach" of the zoo's responsibilities.
A zoo spokeswoman said the viper had still been inside a locked room and the employee who failed to log the incident "no longer works at ZSL".
Other safety concerns at the zoo were also highlighted, including a broken wire in the spider monkey area. The tanks where carpet pythons were kept were also found to be too small for the size of the animals.
But, according to the Daily Mail, overall inspectors from the Department for the Environment, Farming and Rural Affairs, said they were "impressed" by their findings, adding that the animals were in excellent health and that knowledge of the zookeepers was "excellent".
David Field, ZSL's zoological director, told the Evening Standard: "We work closely with the inspection team to make changes immediately or as soon as is possible."
Its venom is primarily haemotoxic, with victims experiencing severe pain and swelling of the bitten area, as well as blisters; the pain of the wound may last for a few days.
A bite can also cause renal and cardiac failure, but fatalities have not been reported.
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