German police arrested three anti-Israel activists on Sunday after they replaced a German flag with a Palestine Liberation Organization (PLO) flag outside the parliament building in Berlin, protesting the government's policies toward Israel and its response to the war in Gaza.

According to the Anadolu news agency, citing Berlin police, authorities opened an investigation into the incident on suspicion of insulting the German state and its national symbols.

The organization responsible for the demonstration, Peacefully Against Genocide, said the flag replacement was intended to express solidarity with Palestinian Arabs and protest what it characterized as the German government's failure to respond to alleged genocide and serious human rights violations in Gaza.

In a statement, an activist identified only as Aaron accused governments around the world of abandoning their responsibility to represent their citizens by remaining silent about, permitting or supporting genocide.

“No matter where in the world a genocide is committed, it affects us all," Aaron said. “We must not shirk our responsibility to stop crimes against humanity."

Referring to the pledge of “never again," the activist questioned whether international commitments to prevent atrocities had any meaning if governments failed to uphold them.

“What does international law mean if governments do not abide by it? What are human rights worth if they do not apply to everyone?" he said.

The organization pledged to continue demonstrating against Germany's relationship with Israel, particularly its military assistance and weapons exports.

It also demanded that German defense manufacturer Rheinmetall suspend all deliveries to Israel and shut down its facility in Berlin.

The protest followed remarks several days earlier by German Chancellor Friedrich Merz, who warned that Muslim immigrants unwilling to acknowledge Germany's historical responsibility for the Holocaust should leave the country.

Speaking at a Berlin reception honoring Jewish athletes participating in the Maccabiah, the international Jewish sporting competition held every four years in Israel, Merz addressed rising antisemitism and concerns about the safety of Germany's Jewish community.

"This historical responsibility of our country applies just as much to those who come here to Germany from Islamic countries," Merz said, according to the dpa news agency. "And anyone who fails to abide by this must leave our country."

Merz has maintained his support for Israel and rejected allegations that its military operations against Hamas in Gaza constituted genocide.

Nevertheless, his government imposed an arms embargo on Israel last year before lifting the restrictions in November.

Germany has also opposed several international measures directed against Israel. In July, Berlin strongly criticized Turkish Foreign Minister Hakan Fidan after he described Israel as a “burden".

Later that month, Merz reiterated that Germany would not support sweeping European Union sanctions against Israel, despite expressing reservations about certain Israeli government policies in Judea and Samaria.