Two more hospital patients have died in an outbreak of listeria linked to pre-packed sandwiches.
Public Health England (PHE) said the victims were among nine patients affected in England.
The death of two of patients from Manchester Royal Infirmary and another patient at Aintree Hospital had already been confirmed by the investigation.
PHE has identified three further cases of listeria, in addition to the original six.
Sandwiches and salads from The Good Food Chain linked to the outbreak have been withdrawn and production stopped.
The chain – which supplied 43 NHS trusts across the UK – had been supplied with meat produced by North Country Cooked Meats, which subsequently produced a positive test result for the outbreak strain of listeria.
PHE said it had been analysing previously known cases of listeria from the past two months to see if they were linked.
All of the cases were found in hospital patients in England and all but one of the fatalities happened more than a month ago.
“To date, there have been no patients linked to this incident outside healthcare organisations, but we continue to investigate,” Dr Nick Phin, of Public Health England, said.
“Swift action was taken to protect patients and any risk to the public is low.”
He added: “PHE is continuing to analyse all recent and ongoing samples of listeria from hospital patients to understand whether their illness is linked to this outbreak.”
A listeria infection can cause a small amount of discomfort but is more likely to seriously affect pregnant women, the elderly and those with a weakened immune system.