Golden Dawn
Supporters of Greece's far-right Golden Dawn party take part in a rally in Athens (Reuters)

A violent childhood of Nazi salutes, firearms and hate speech has been revealed by Greek detectives investigating the far-right Golden Dawn party.

Police raided the houses of Golden Dawn's leader Nikos Michaloliakos, party spokesman Ilias Kasidiaris and other lawmakers with the xenophobic party who are facing trial in Athens on charges of participating in a criminal organisation.

The officers uncovered a plethora of incriminating photos and videos on personal computers, mobile phones and data storage sticks.

Some images leaked to the press revealed Golden Dawn's close ties with the Nazi ideology, something the party has long denied.

Among the most troubling material was video footage showing a Golden Dawn member holding a propaganda seminar for children and teaching them how to draw a swastika.

A child was depicted as mimicking a Nazi salute in another photo.

Other material showed party members wearing a Ku Klux Klan outfit and carrying out paramilitary exercises in rural areas of the Mediterranean country.

Kasidiaris was depicted overseeing men wearing military gear doing press-ups and firing a number of weapons at shooting ranges or in country fields.

The 33-year-old was also seen posing for a group picture amid a group of bare-chested men making the Nazi salute.

Kasidiaris, Michaloliakos and another MP have been detained in pre-trial custody since September, following a crackdown on the far-right group that followed the killing of anti-fascist rapper Pavlos Fyssas.

Newspaper Ekathimerini reported that, based on the seized material, prosecutors are considering pressing further charges of treason against the lawmakers.

Michaloliakos was heard allegedly inciting an audience to overthrow Greece's democratic system in another video retrieved by police.

"They say that we, nationalists, are bad fascists. The truth is that they are not wrong. Our goal is not to improve those who are in Parliament today, to fix the political forces that are corrupt and at their end, but to finish them off, once and for all," Michaloliakos is allegedly heard as saying.

"Those who complain but won't get up off their couches are worms and we will crush them underfoot like worms." another Golden Dawn member allegedly told a party meeting.

"Others swing between the left and right, but we don't care that they're swinging because they'll be swinging by their necks."

Golden Dawn has made substantial gains from Greece's deep economic crisis, blaming the country's large immigrant population as one of the causes.

It won 18 seats in the Greek parliament, gaining almost 7% of preferences in the two elections last year. Half of its lawmakers are now facing criminal charges.