WARSAW, Poland (AP) — A Polish historian resigned Monday from the government's historical institute after controversy erupted over his past ties with a far-right organization and photos of him making the stiff-armed fascist salute.

Tomasz Greniuch was recently appointed to head the Wroclaw office of the Institute of National Remembrance (IPN), a state organization whose role is to investigate Nazi and communist era crimes.

The head of the institute, Jaroslaw Szarek, said in a statement Monday that Greniuch offered his resignation and it had been accepted. Szarek said the circumstances surrounding the appointment had made it impossible for Greniuch to do his job.

Outrage had been mounting over the appointment in Poland, a country that suffered enormously under Nazi German rule in World War II. However, the fact that Greniuch was even named to his role was seen by some as how right-wing extremism has become mainstream under the Poland's conservative ruling Law and Justice party.

Greniuch issued a public apology on Friday for his youthful behavior.

“I have never been a Nazi. I apologize once again for the irresponsible gesture from several years ago and I consider it a mistake,” he said, describing his past behavior as “youthful bravado.”

A spokesman for his office said Greniuch, who is in his late 30s, was not available Monday to comment.

Officials close to both President Andrzej Duda and Prime Minister Mateusz Morawiecki had signaled that Greniuch should be dismissed.

“For the sake of the institution and image of Poland, there should be a change in the position of the head of the Institute of National Remembrance in Wroclaw,” Michal Dworczyk, a top aide to Morawiecki, said earlier Monday.

Outrage in Poland has grown as images have been published in the media of Greniuch making the stiff-armed solute in 2005 and wearing the T-shirt of the National Radical Camp, a far-right group that traces its roots to an anti-Semitic and openly fascist movement which existed before World War II.

Greniuch had already been posted to the head of the IPN office in the southwestern Polish city of Opole three years earlier.

In a 2019 radio interview, he said he had not cut himself off from his earlier views but had changed his behavior.

"When you have your dream job, you try to be a professional," he said.