Preston Police have launched an appealed after an 83-year-old man was punched in the face and robbed.
Officers want to speak to Patrick Jackson in connection with the incident, which happened on Friday (6 January) in Walker Street.
51-year-old Jackson is 5ft 7in tall and of medium build.
He has links to the city centre and could be violent if approached.
Read more: Two teenagers charged with robbery in Ashton-on-Ribble
A 48-year-old man, of no fixed address, has been arrested on suspicion of robbery and is in custody.
Anyone with information should call police on 01772 209940 or email 2954@lancashire.police.uk. In an emergency always call 999.
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