Melioidosis, a bacterial infection, was responsible for killing at least nine monkeys at a Hong Kong zoo, authorities said, as a further two died over the weekend, taking the total to 11 in the past week.

A recent spate of monkey deaths at a Hong Kong zoo warrants a review of biosecurity protocols by an external organisation and soil surveillance for bacteria linked to the fatalities, animal health and microbiology experts have said.

A 11th monkey from the Hong Kong Zoological and Botanical Gardens was found dead on Sunday whilst under quarantine, the government has said. In a statement issued on Sunday evening, the government said a common squirrel monkey died while being placed under isolated surveillance.