BERLIN (AP) — One of the founders of the German anti-immigration group PEGIDA went on trial Tuesday, charged with incitement over Facebook posts in which he allegedly called foreigners "cattle" and "trash".

Lutz Bachmann's trial at the district court in the eastern city of Dresden is scheduled to last until May 10. Incitement can carry a prison sentence of up to five years.

Bachmann is accused of trying to incite Germans against refugees with the September 2014 social media posts.

Bachmann expressed regret shortly after the postings — and photos of him posing as Adolf Hitler — surfaced. He described them as "ill-considered comments that I wouldn't make in this way today" and apologized for harming PEGIDA.

Bachmann has denied the charges, saying the trial is "purely politically motivated" and meant to discredit him and the group.

As Bachmann's trial opened, supporters staged a protest outside the court bearing banners calling for "freedom for Lutz Bachmann". Opponents, chanted "Bachmann in the slammer".

PEGIDA, whose German acronym stands for Patriotic Europeans against the Islamization of the West, has dismissed claims that it cooperates with neo-Nazi groups, though far-right extremists regularly take part in its weekly protests in Dresden, the capital of Saxony.

The state has become a hotbed of anti-immigrant violence in recent years. Authorities arrested five people in Saxony on Tuesday on suspicion of founding a right-wing terror group to attack refugee homes and other facilities. The "Freital Group", named after a suburb of Dresden, was formed in July last year or earlier.