Umashima has more cats than people but numbers have fallen by two-thirds, with pieces of poisoned fish suspected

Authorities on a remote island in Japan where there are more cats than people appear close to solving the mystery behind a dramatic drop in its feline population.

Animal welfare groups voiced concern that foul play was responsible after the number of cats on Umashima, an island of 30 people about 10km (six miles) off the south-western city of Kitakyushu, fell from 90 in 2014 to just 30 this year.

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