ATHENS, Greece (AP) — Thousands of police officers have been deployed in Athens and the northern Greek city of Thessaloniki to prevent gatherings to mark the anniversary of the crushing of a 1973 student uprising against Greece's military junta.

Nov. 17, the day the uprising was quashed, is marked each year with wreath-laying ceremonies at the Athens Polytechnic commemorating those who died there, followed by marches to the U.S. Embassy. The United States had backed the dictatorship that ruled Greece for seven years from 1967.

But the Greek government has banned the marches this year, citing public health concerns as the country struggles to contain a resurgence of the virus that is straining hospitals and leading to record numbers of deaths. Authorities have banned gatherings of more than three people from Nov. 15-18 nationwide.

Left-wing opposition parties decried the ban but a late challenge at Greece’s highest administrative court, the Council of State, to declare the ban unconstitutional was unsuccessful.

A Communist Party-backed union defied the ban, gathering briefly Tuesday near the U.S. Embassy, which was blocked off by police buses. The protesters, reportedly numbering about 200, wore masks and maintained social distancing, standing in formation.

"The Polytechnic lives, out with the Americans!” they shouted.

Other left-wing groups and anarchists have also vowed to defy the police ban on gatherings later in the day. The annual Polytechnic marches often turn violent, with protesters clashing with riot police.

The union gathering came as Prime Minister Kyriakos Mitsotakis laid a wreath at the Athens Polytechnic amid tight security.

“Every important anniversary gains new meaning through the conditions in which it is celebrated,” Mitsotakis said, adding that current priorities were protecting public health and showing solidarity with young people affected by the financial crisis.

Greece is under lockdown until Nov. 30 as authorities struggle to contain a coronavirus resurgence that has seen infections spike across the country. On Sunday, Greece recorded its largest coronavirus death toll in a single day: 71.

The European Union nation of 11 million people now has more than 76,000 confirmed cases and more than 1,100 deaths, while its intensive care units are at 78% capacity.

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