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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A call centre worker from Tredegar, accused of downloading so-called Islamic State manuals, has been ordered to stand trial in the summer.
A minute's silence will be held to remember the four men who died in the Didcot Power Station collapse a year ago.
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