March 12 (Reuters) - Britain's vets could face a formal market investigation by the country's competition regulator after an initial review raised multiple concerns about the sector.

Concerns that pet owners might not be getting a good deal prompted the Competition and Markets Authority (CMA) to start looking into the veterinary market last September.

This review flagged several concerns including pet owners potentially overpaying for medicines and weak competition, partly because of sector consolidation.

Since 2013, 30% of the 5,000 vet practices in Britain have been bought by six firms - CVS Group, IVC, Linnaeus, Medivet, Pets at Home and VetPartners - the CMA said.

News of the CMA's provisional decision hit shares, with Pets At Home dropping to 252.2 pence, its lowest level since July 2020, while CVS Group tumbled 19.1% in early trading on Tuesday.

"Given these strong indications of potential concern, it is time to put our work on a formal footing," CMA chief Sarah Cardell said in a statement.

The CMA said it will seek views from the sector on its proposal to launch a formal investigation and decide on its next steps after its consultation closes on April 11.

CVS Group said it had already put forward a package of possible remedies to address the CMA's concerns along with certain other corporate groups.

"CVS continues to believe this package could be adopted across the market and could address the CMA's concerns more quickly than an 18-month investigation," it said. (Reporting by Yadarisa Shabong and Eva Mathews in Bengaluru; Editing by Rashmi Aich, Sherry Jacob-Phillips and Alexander Smith)