German Chancellor Angela Merkel on Monday denounced the burning of Israeli flags to protest against the United States' decision last Wednesday to recognize Jerusalem as Israel's capital.

"We oppose all forms of anti-Semitism and xenophobia," she said following a meeting of senior members of her Christian Democratic Union (CDU) party in Berlin. She added that "the state has to use all available legal measures" to combat these actions.

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On Sunday, some 2,500 demonstrators marched through Berlin's Neukölln district and burned flags with the Star of David, the Berliner Zeitung reported, to demonstrate against the controversial decision by US President Donald Trump.

Eleven people were detained and cited for offenses, including illegally covering the face, police said.

On Friday, around 1,200 anti-Israel and anti-American protesters gathered at the Brandenburg Gate in Berlin, near the US Embassy,

The Berliner Zeitung reported the 12 people are being investigated for disturbing the peace and violating laws prohibiting the desecration of the flags of foreign states. Police said 10 people were detained.

Flag burning 'unacceptable'

Germany's interior minister has also criticized the burning of Israeli national symbols in Berlin.

"We don't accept it when Jews or the state of Israel are disgraced in this way," Thomas de Maziere told the Monday edition of mass daily Bild. Germany is "bound in a special way to the state of Israel and people of Jewish belief," he said.

He added that freedom of speech and protest is respected, but those rights must be carried out peacefully.

At least 20 people were detained during protests over the weekend

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German Foreign Minister Sigmar Gabriel told Bild that despite understandable criticism of the US decision, "there is no right and also no justification to burn Israeli flags, incite hatred against Jews or question the right of Israel to exist."

Whoever does such things, Gabriel said, "is not just opposing Israel but also the constitutional order of Germany."

Justice Minister Heiko Maas also said there was no place for any sort of anti-Semitism.

amp, cw/cmk (AFP, dpa, kna, Reuters)