The number of employees at a Bernard Matthews meat production factory testing positive for coronavirus has risen to 25 with the company suggesting the outbreak may be linked to workers car sharing.

The staff and their contacts, all working at the company’s turkey processing plant in Holton, near Halesworth, are now self-isolating at home.

The majority are living in the Great Yarmouth and Lowestoft areas.

The company, which employs about 1,000 people at the site, said some cases from homes from which people shared cars into work.

The BBC reported that Andrew Sherwood, Bernard Matthews’ human resources director has written to the Unite union, which represents workers at the plant, that: “At present, there are 25 positives and 54 are self-isolating.”

“Many of those self-isolating have now been tested at home and are negative, but must remain self-isolating for 14 day as per Government guidelines.”

MORE: Testing continues after Bernard Matthews workers found to have coronavirusBernard Matthews is working with both local and national public health officials to look at key information on each case such as address, transport, work location and family and social links to other employees.

Mr Sherwood said: “This information enables us to quickly identify colleagues that need to self-isolate.”

No clear link had been established between any of the cases “at site and the cases appear to have come from a limited number of addresses in Lowestoft/Great Yarmouth from which people car shared”.

In a joint statement issued on behalf of Public Health Suffolk, Public Health Norfolk, Public Health England and Bernard Matthews, it has been confirmed that approximately 100 members of staff had been tested, with most returning negative results, while additional testing is taking place this week.

Food production and safety is unaffected by the cases being identified, with the factory entering its busiest time of the year.