The warning follows an incident where a man masquerading as a police officer from Hampshire Constabulary conned an equine physiotherapist.
The caller said he was collecting sponsorship to help publish a magazine about horse thefts.
The female victim, from the Waterlooville area, only found out she had been conned after the money had been debited from her account.
Hampshire Constabulary is now urging the equestrian community to be vigilant following the incident, which happened on November 17.
Anyone with information relating to this incident, or have received a similar call, should contact the police on 101.
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