MADRID (REUTERS) - Coronavirus cases in Spain jumped by nearly 1,700 on Wednesday (Aug 12), part of a surge that has prompted the construction of a military field hospital in the hard-hit Aragon region and led authorities in Galicia to practically ban smoking in public places.

Health ministry data showed 1,690 new coronavirus cases were diagnosed in the 24 hours to Wednesday, up from the 1,418 reported on Tuesday and bringing the cumulative total to 329,784. The new daily number excluded Madrid, which did not provide fresh data due to technical difficulties.

Since lifting its strict lockdown around six weeks ago Spain has struggled to keep a lid on new infections, with average daily cases rising from less than 150 in June to more than 1,500 in the first 12 days of August.

In scenes reminiscent of the epidemic's March-April peak, TV footage showed air force personnel setting up dark green tents to serve as a field hospital in Zaragoza, Aragon's regional capital in northeastern Spain.

Set to open on Friday, the facility attached to Zaragoza's University Clinic hospital will be used as a triage centre and temporary ward, the air force said in a statement.

With 571 cases per 100,000 inhabitants, Aragon has the highest prevalence of the virus in Spain. Navarre, with the second-highest rate, has just 159 cases per 100,000 people.

Despite having some of the lowest levels of the virus, northwestern Galicia issued a blanket ban on smoking on the street and on restaurant terraces when social-distancing cannot be guaranteed.

Under Spain's decentralised government, each region is largely in charge of its own response to the virus, leading to a patchwork of different restrictions and preventative measures.

Wealthy northeastern Catalonia is set to expand a mass-testing program in the coming days to include several neighbourhoods of its capital, Barcelona.