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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The Royal London One-Day Cup match being played in Cardiff has been abandoned due to a 'dangerous pitch'.
A series of crashes on the A470 have led to traffic disruption
A largely dry and warm afternoon, but a muggy night to come with showery outbreaks.