The three businesses, which include a bar and a hairdresser, were hit with 1,000-euro ($1,166) fines after police found they had not respected an edict imposed on Friday that requires people to wear masks in enclosed spaces. 

"If our fellow citizens think that the problem is resolved, that means that within a few weeks we will return to a grave emergency," Vincenzo De Luca, the president of Campania, which includes Naples, posted on Facebook on Friday.

"We knew that there would be an increase in contamination, it was widely expected," he said, a few hours before the publication of an order toughening the rules to fight against COVID-19 pandemic.

The key measure of the text is a fine of 1,000 euros for anyone who does not wear a mask in an enclosed space, whether in public buildings, supermarkets, bars, restaurants, shops or on public transport.

According to the new regulations, "transport operators are required to deny access to passengers who do not wear the mask". 

If they are on board, they must be sanctioned and "invited to disembark immediately or as soon as possible". If they refuse, "the bus or train will be blocked" and the "intervention of the police will be requested".

Businesses are also being held responsible "if the offence is committed in the exercise of a commercial activity". 

Apart from a 1,000-euro fine, the business could face closure from five to 30 days. 

Italy was the first country in Europe to be affected by coronavirus. More than 35,000 people have died and there have been over 242,000 cases of contamination. 

Saturday saw 275 new cases as well as five deaths.