Greek police on Sunday announced a ban on public gatherings of four or more people as hospitals were overwhelmed with coronavirus cases, ahead of the annual anniversary of a 1973 anti-junta uprising.
Greece on Saturday said it would shut primary schools, kindergartens and daycare centres as coronavirus deaths crossed a thousand.
The anti-junta demonstration is a treasured anniversary for many Greeks, and more than 30,000 people demonstrated in Athens and other major cities last year under a heavy police presence.
At least 24 people were killed in the 1973 crackdown, an event generally considered to have broken the junta's grip on power and helped the restoration of democracy.
This year, however, all public gatherings of four or more people would be banned from 6 am on Sunday to 9 pm on Wednesday to stem the spread of coronavirus, police said in a statement.
Fines of 5,000 euros will be issued to legal entities like political parties and 3,000 euros for individuals who organise gatherings, while those participating will be fined 300 euros.
Citizens' Protection Minister Michalis Chrysochoidis said on Friday that the events and marches commemorating the November 17 Athens Polytechnic student uprising will not take place this year.
"We did not celebrate March 25th or October 28th, we did not celebrate Easter, we did not celebrate any of the things that unite us in 2020. The same will be the case with the Polytechnic anniversary," the minister said, referring to three national holidays that were not celebrated because of the coronavirus pandemic.
"The virus is the enemy and large gatherings are its main weapon," he added, prompting opposition parties to pledge they would proceed with demonstrations.
Communist KKE party leader Dimitris Koutsoumpas in an interview on Saturday stressed that "the Polytechnic march was never organised by the government".
"All the measures will be strictly observed with the use of face masks and antiseptics, keeping the necessary distances and of course we urge people belonging to vulnerable groups or those who are ill to stay at home," Koutsoumpas said.
Greece's former finance minister Yanis Varoufakis, leader of the Diem25 party on Saturday accused the government of announcing in advance the arrest of his party's members.
On Friday, Greek police evacuated the premises of the historic Polytechnic building that now houses the National Technical University of Athens and another university campus and arrested 92 people for trespassing, disturbance and disorder.
Authorities on Saturday reported 2,835 new coronavirus cases, taking the total to 72,510, and 38 new deaths, raising the toll to 1,035.