ITV said the programme was the highest rating show of the year so far, nudging ahead of a Coronation Street which pulled in 11.2 million in January.
Adding viewers for ITV's +1 channel brought the audience to 11.9 million for the BGT finale, with a peak audience of 14.5 million.
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Friday afternoon's forecast for the east of the region
Friday afternoon's forecast for the west of the region
Two men have been jailed for more than four years each after attempting to smuggle 18 Albanian immigrants into the UK.