Marc Thompson said the "hardest thing is not knowing" where his twin brother Ben is.
The 34-year-old from Haverfordwest has been missing since Saturday, after he watched Wales' Six Nations game at the Millennium Stadium.
He told our Correspondent Carole Green that this would be "very out of character" for him not to contact his family.
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Window cleaner Gavin Tainton tied up the 88 year-old woman with electric wire and left her for dead at her home where she lived alone.
The price of first and second class stamps is to increase by 1p each to 63p and 54p from March 30, the Royal Mail announced today.
New figures show that heart disease and dementia are the leading cause of deaths for people in England and Wales in 2013.