The authorities in Mauritius have held Italian passengers on board an Alitalia flight arriving from Rome, and have told them that anybody coming from the northern Italian regions worst affected by coronavirus must either go into quarantine or return home.

Alitalia says it's arranging for the immediate repatriation of all 40 passengers coming from the Lombardy and Veneto regions, even though none are showing any symptoms.

In Italy, 11 northern towns are under lockdown, after more than 2,000 residents tested positive. Five people have died.

Churches and schools have been closed; Milan's Fashion Week and the Venice Carnival have been cancelled.