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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Paula Hooper was confronted with a knife-wielding robber at her post office in Ely.
Lorraine Ridout, a grandmother from Cardiff, has been missing for nine months.
The RSPCA in Wales is expecting to receive thousand of calls about animal neglect this winter.