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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Wales Captain Sam Warburton says his team are raring to go as they kick off their Six Nations campaign in Dublin tomorrow.
Liberal Democrat leader Tim Farron has criticised Labour at the party's spring conference in Cardiff.
A Royal Gun Salute was held at Cardiff Castle earlier today to mark the 64th anniversary of the Queen's accession to the throne.