Greece has pledged that migrants made homeless after devastating fires at Europe’s biggest refugee camp will be rehoused on the island “within days” in defiance of fierce opposition from locals.

The country’s migration minister Notis Mitarachi said the process of resettling more than 12,500 men, women and children forced to flee the facility in Lesbos was well under way even if the coronavirus pandemic meant it was also taking longer.

“It will take a few days but all the affected people will be moved into this temporary location behind me,” he told reporters at the site where authorities, with the aid of the army, have been racing to set up tents. “We hope to have 5,000 beds ready by the end of the day.”

Rapid Covid-19 tests were being conducted before anyone entered to ensure it remained “a safe community”, Mitarachi said. Erected in a former firing range within view of the sea, the replacement camp is the government’s answer to the humanitarian emergency that exploded last week after fires erupted in the now-gutted holding centre in Moria.

A series of blazes, starting on Tuesday, decimated the notoriously overcrowded facility forcing thousands of people into the surrounding countryside. In the chaos that ensued refugees have slept rough, many in makeshift shelters along the side of a stretch of road leading to Mytilene, the island’s port capital, under heavy police guard.

Others had sought refuge in olive groves, churches, supermarket parking lots and even a local cemetery, as authorities and aid groups struggled to bring in water and food. The prospect of being relocated to a new site has been welcomed neither by the refugees, nor locals.

Lesbos, which faces Turkey, has long been on the frontline of refugee arrivals. Close to a million displaced Syrians landed on its shores in dinghies and rickety boats at the height of the country’s civil war when Europe’s migrant crisis peaked.

For migrants forced to endure lengthy waits for requests to be processed, the Aegean isle is not the promised land envisaged when they embarked on the often perilous journey to Europe.

On Sunday, a day after riot police fired teargas at protesters, many refused to enter the new site for fear they would never leave. Mitarachi insisted that those remaining outside would not be transferred to the mainland. “The best solution for them to move on with asylum applications is in the camp,” he said, claiming the centre-right government’s migration policies were “tough but fair”.

Fears of a surge in coronavirus cases has, say authorities, made it ever more vital that people living at the camp are found and tested. Prior to the infernos, 35 of Moria’s residents had been diagnosed with the virus, with the Greek migration minister telling reporters “there might be 200 cases … by now”.

In Thessaloniki the Greek prime minister, Kyriakos Mitsotakis, said the combination of the pandemic and the migration crisis had made for “an explosive mix” and blamed the fires on “overactive asylum seekers” hoping Moria’s destruction would see them being moved to Athens.

But he also voiced optimism that the end of a facility long deplored by human rights groups for its appalling conditions could mark the beginning of a new era for Europe in its often bungled handling of the issue.

“I want to believe that this tragedy is a warning bell for all,” he said, adding that, whatever happened, a new camp would be built on Lesbos with the help of Europe. “I’ve requested that the EU be involved in the management of the new centre wherever it is [on the island]. I’d like to see the flag of Greece and Europe flying from masts at it.”

Athens has long complained that, aside from funds, it has received little solidarity from the 27-member bloc. “We can’t fail a second time as Europe in handling the migrant crisis,” Mitsotakis said.