South Wales Police says a body has been found in the River Ely, near Penarth Road in Cardiff.
Formal identification has not yet taken place.
The family of 34-year-old Ben Thompson from Haverfordwest, who has been missing for more than a month after watching Wales play in the Six Nations, has been informed and are being kept updated by family liaison officers.
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Some very wet weather will sink it's way south and east overnight, with mist and murk developing around coasts.
The Wales Rugby squad are currently in Switzerland at a gruelling conditioning training camp ahead of the World Cup in September.
Wales joined the rest of Britain today in falling silent to remember those who were killed in the July the 7th bombings.