Three people have been arrested as part of a joint Victoria Police and Racing Victoria raid on the stables of champion horse trainer Darren Weir.

Officials are currently at a property at Miners Rest in Ballarat and a stable in Warrnambool, the Ballarat Courier reported on Wednesday.

Racing Victoria confirmed the raids followed an earlier investigation, also details of the initial inquiry remain unclear.

“Racing Victoria's Integrity Services team has been conducting an investigation into the activities of licensed persons in the Warrnambool and Ballarat areas,” executive general manager of integrity Jamie Stier, said in a statement.

“During the course of our investigation, we sought the support of Victoria Police's sporting integrity intelligence unit on the matter, instigating their investigation.”

Three people have been arrested for questioning.

“As the matters are the subject of on-going investigations by Victoria Police and Racing Victoria we are not at liberty at this time to disclose the identities of the persons arrested nor the details of the investigations,” Mr Stier said.

“Racing Victoria is committed to maintaining the highest integrity standards in our sport and, where appropriate, we will continue to work with Victoria Police on those investigations.”

Victoria Police have been contacted for comment.

Weir is one of Australia's best-known horse trainers and was behind the 2015 Melbourne Cup winner Pirate of Penzance.

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