The Hollywood star - famous for roles in The Fresh Prince of Bel-Air and Men in Black - met students at St Martin-in-the-Fields High School for Girls in Tulse Hill, doing a question and answer session and signing autographs.
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Staff in the banking and finance sector said they expect their annual reward to rise by an average of 21%.
Tonight, staying windy with gusty southwesterlies, remaining mild and mostly cloudy.
The notices have been posted in Covent Garden are thought to be aimed at organised criminal gangs.