Authorities in Ticino, which borders hard-hit Italy, announced during a news conference that all restaurants, bars and shops with the exception of food stores and pharmacies, would close from Sunday.

The canton, like the rest of Switzerland, already decided on Friday to shut down schools and limit public gatherings in a bid to halt the spread of the deadly new coronavirus.

Entry from Italy, where more than 1,250 people have died from the virus, was also largely limited to Swiss nationals and residents, and Swiss media reported a 60-percent decline in crossings into Ticino Saturday.

Controls at Switzerland's borders with other surrounding countries have also been tightened, but no similar entry limits have been imposed.

The army meanwhile said it was preparing to deploy one of its four hospital battalions to help hospitals across Switzerland cope with the outbreak, which has killed a dozen people and infected more than 1,350 country-wide.

Army chief Thomas Sussli said in a tweet overnight that the battalion, which counts many with "basic care training", would carry out a "special service towards the security and protection of us all."

Army spokesman Daniel Reist told AFP that the battalion, made up of between 500 and 600 personnel, will be prepared to support work at hospitals across the country if requested, especially taking on logistical tasks.

"There has not yet been a request," he said.

The army in Switzerland is organised as a militia, with conscripts carrying out a short initial training and then being called back in for several weeks of training each year.

It also counts doctors and specialists in its ranks, but they have been asked to remain in their civilian positions.

The army has already deployed 23 people to support two hospitals in Ticino, Reist said.

The army also said Saturday it would halt all recruitment activity until further notice to protect conscripts and military personnel from the virus.

The Swiss government meanwhile warned that cybercriminals had begun sending out emails purportedly from the country's health ministry, playing on people's anxiety over the pandemic to try to infect their computers with malware.