Tourists wearing protective respiratory masks tour outside the Colosseo monument (Colisee, Coliseum) in downtown Rome on Jan 31, 2020. (ALBERTO PIZZOLI / AFP)

MILAN - Three people have tested positive in Italy for coronavirus, the northern Lombardy region said on Friday, the first known cases of local transmission of the potentially deadly illness in Italy.

Looking to prevent a further spread of the virus, officials urged residents of the northern towns of Codogno and Castiglione d’Adda to stay at home and avoid any social gatherings.

Looking to prevent a further spread of the virus, officials urged residents of the northern towns of Codogno and Castiglione d’Adda to stay at home and avoid any social gatherings.

“We have introduced a compulsory quarantine for all those who have been in contact with the patients who tested positive,” Italian Prime Minister Giuseppe Conte told reporters, adding that anyone who had been in “areas of risk” over the past two weeks should stay at home.

Giulio Gallera, a member of the Lombardy regional government, said the initial patient fell ill after meeting a friend who had recently returned from China. He was now in intensive care.

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The other two infected people were the wife of the 38-year-old-man and one of his friends. None of the trio had themselves been to China.

Local authorities were tracking down everyone they had come into contact with and around 100 people were being tested for the virus.

“Most of the contacts of those tested positive for coronavirus have been identified and subjected to the necessary tests and measures,” the region said in a statement.

Prior to Friday, just three people had been confirmed in Italy to have the virus.

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Two Chinese tourists who came from Wuhan tested positive in Rome in late January, while an Italian who returned from the Chinese city of Wuhan with a special flight repatriating some 56 nationals was hospitalized a week later.