A confident far-right Alternative for Germany has set up its new youth organization as thousands of protesters converged on the western city of Giessen.

Germany’s foreign ministry has hit back at U.S. Secretary of State Marco Rubio after he criticized the decision to classify the Alternative for Germany party as a “right-wing extremist” organization.

Four candidates are bidding to be Germany’s next leader in Sunday’s election.

Projections show that Germany’s unpopular governing parties sank to feeble results and the far-right Alternative for Germany made gains in Sunday’s vote for the European Parliament, while the mainstream conservative opposition was the country’s strongest political force by a distance.