Health officials investigating an outbreak of salmonella infection today revealed the number of people struck down by the illness continued to rise.

Up to last night, there were 69 confirmed cases of the food bug and 14 suspected cases. The outbreak is centred on Derwentside, County Durham. Three patients were being treated in hospital.

Outbreak Control Team chairman Dr Deb Wilson said: "The outbreak team would like to reassure members of the public that effective measures have been put in place.

"However, we anticipate that further cases of salmonella, in people who may have eaten contaminated food before the control measures were put in place, will continue to come to light over the next few days.

"We are working with local doctors and are being notified of suspected salmonella cases which, as usual, we then investigate to identify any possible link."

Dr Wilson said investigations were ongoing into the possible source of the outbreak, but the findings so far continued to support a possible link with Robson's Fresh Foods in Stanley.

Robson's Fresh Foods is continuing to co-operate fully with Derwentside District Council and has been closed since the afternoon of Thursday July 29, when the council served a prohibition notice.

Salmonella infections cause a range of symptoms, including diarrhoea, abdominal pain, headache, nausea, vomiting and fever.

If members of the public have or develop severe diarrhoea or have diarrhoea lasting more than 48 hours, they should ring NHS Direct on 0845 4647 or their usual GP or out of hours service.