Thousands took to the streets of Greek capital of Athens on Monday to mark a 1973 student uprising that helped topple the military junta.

Demonstrators have marched to the US Embassy every year since 1974 in protest of Washington's support at the time of the dictatorship in Greece.

Thousands of riot police were deployed, and main arteries closed to traffic, as well as metro stations along the march route.

In 1973, the military regime that had been in power since 1967 sent police and troops to crush student-led pro-democracy protests centred at the university.

Officers opened fire on unarmed demonstrators and bystanders, and an army tank smashed through the gates of the Polytechnic, behind which many students had gathered.

At least 20 people are believed to have been killed, although the exact death toll of the November 1973 events has never been definitively determined.

The uprising was followed by a putsch within the junta which brought even harder-line officers into power.

Democracy was restored in Greece in July 1974, after the dictatorship collapsed in the face of a Turkish invasion of Cyprus, provoked by the junta's own machinations aiming to unite the island, whose majority population is Greek-speaking, with Greece.

AP video shot by: Srdjan Nedeljkovic