Germany’s far-right Alternative für Deutschland (AfD) came under attack on Wednesday during a heated Bundestag debate, accused of “blaming immigrants for everything”.

Two recent deaths in eastern Germany involving asylum seekers have prompted the AfD to organise “mourning” marches or support demonstrations of neo-Nazi groups – including illegal Hitler salutes and cheers of “Nationalism Socialism: Now!”

But AfD joint leader Alexander Gauland defended in the Bundestag the marches of “concerned citizens” and said the “regrettable” Hitler salutes were the work of a few “empty heads”.

“The real crime was the bloody act committed by two asylum seekers in Chemnitz,” he added, referring to the fatal stabbing two weeks ago of a German-Cuban man in the eastern German city earlier this month

Two suspects – Syrian and Iraqi asylum seekers – are in custody. Last weekend, meanwhile, a 22-year-old German man died of heart failure in the eastern town of Köthen after intervening in a fight among Afghan immigrants.

Schulz accusations

Leading the parliamentary attack on the AfD was ex-Social Democrat (SPD) leader Martin Schulz. He accused the far-right populist party of flirting with fascist methods by reducing everything in German politics to the migration question.

“Migrants are to blame for everything,” he shouted. “We had a similar language in this chamber once before.”

He also took a swipe at Mr Gauland, who referred recently to the 12-year Nazi era as “bird shit” when viewed in Germany’s long history.

“A collection of bird shit is a dung heap, and you belong on the dung heap of history,” said Mr Schulz, to a standing ovation from his party colleagues. “It’s time for democracy to defend itself against these people.”

Mr Gauland protested he had nothing to do with fascism and that the attacks from Mr Schulz were “beneath his dignity”.

After another attack from the SPD benches the AfD walked out of the chamber in protest.

German chancellor Angela Merkel in the Bundestag. Photograph: Odd Andersen/AFP/Getty Images

Chancellor Angela Merkel took a more moderate approach, saying she understood public concerns after the deaths of the two men.

“But there is no excuse for hate, the use of violence in some cases, Nazi slogans, hostility towards people who look different or who own a Jewish restaurant,” she said, referring to attacks in Chemnitz following the fatal stabbing. Nor would she allow the “clandestine exclusion of entire groups” from German society.

“Jews and Muslims belong as much to our society as Christians and atheists,” she said.

Mockery

The AfD attacked her “general” remarks on the two deaths as a “mockery of the victims of your [immigration] policies”.

The Chemnitz attack has prompted huge soul-searching in German society over immigration, with AfD politicians disputing media claims of attacks on foreigners in retaliation for the attack.

Germany’s intelligence chief expressed similar doubts in a tabloid interview over whether a video posted online, showing two men attacking a third, was authentic or provided enough proof of co-ordinated attacks in Chemnitz on immigrants.

Quizzed on Wednesday by MPs, who accuse him of playing into the AfD’s hands, the intelligence official chief said he was not doubting the video’s authenticity.