South Wales Police say CCTV footage shows him 45 minutes later walking towards wasteland at Lawrenny Avenue.
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2.
Footage shows him crossing Leckwith Road into Lawrenny Avenue, Leckwith, near the Cardiff City Stadium, at 19:17 GMT on Saturday.
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3.
He was seen by friends in Mill Lane in the city centre at about 18:30 GMT and then the last known footage of him captured on CCTV showed him crossing Leckwith Road into Lawrenny Avenue at 19:17 GMT, near Cardiff City stadium.