Greek health officials announced that 262 positive cases of Covid-19 were recorded, marking the single biggest increase in cases since the beginning of the pandemic.

The increase follows strict new measures that were introduced by the government, including the cancellation of all religious services on the August 15 holiday and the forced midnight closure of bars and restaurants in most tourist regions throughout the country.

The government in Athens also placed the Greek island of Poros in a mandatory lockdown following a sudden flare-up of infections of locals and tourists.

“The rising rate has me extremely concerned,” Manolis Dermitzakis, a Greek professor of medicine in the University of Geneva said in an interview with Voice of America. “We’ve seen cases triple in a short period of time in Greece.” And ultimately, he said, it all boils down to the fact that measures are not being fully adhered to by tourists and locals, alike.

Another doctor, Gkikas Magiorkinis, who advises the government on the Coronavirus pandemic, told the Guardian’s Helena Smith in an interview that Greece was “formally” in a second wave of the virus outbreak.

Cases have been increasing steadily in Greece over the past week, alarming officials and jeopardizing the track record of the government during the first three months of the pandemic when a mandatory lockdown and strict restrictions on movement kept the spread of the virus in check.