London Zoo says it believes Melati carried the cub outside, but keepers are unclear as to how the cub got into the pool.
Keepers are now reviewing the situation because it was not forseen that the mother would take the cub outside so early.
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Sunday will be dry with some long spells of sunshine across the region, but feeling colder in the easterly breeze.
Chelsea Football Club has "apologised profusely" to Gary Johnson who was sexually abused and "suffered unacceptably" as a youth team player.
A man has been jailed after his victim was found slumped in a car with stab wounds in east London.