Twelve more patients in England have tested positive for coronavirus, taking the total number of UK cases to 35.
Three patients were close contacts of a known case which was transmitted in the UK, chief medical officer Prof Chris Whitty said.
One person from Essex had “no relevant travel” and it was unclear how they had contracted the virus.
Out of the remaining eight cases, six had recently returned from Italy and two had been to Iran.
On Friday, a man from Surrey became the first person to be infected within the UK.
The patient, who is being treated at Guy’s and St Thomas’ Hospital in central London, had not been abroad recently – unlike the other cases in the UK.