Police arrested 16 people in two separate incidents at synagogues in the cities of Bonn and Münster, where Israeli flags were set on fire late Tuesday.
Josef Schuster, president of Germany’s Central Council of Jews, blamed Hamas for the escalating conflict in Israel and said tensions were spilling over.
“Israel and Jews as a whole are subjected to hatred and incitement, particularly on social media. The threat to the Jewish community is growing,” he said.
Pointing to the flag-burning incidents, he said “the protection of Jewish institutions must be raised”.
“We expect from the people in Germany solidarity with Israel and the Jewish community,” added Schuster.
Anti-Semitic crimes have risen steadily in Germany in recent years, with 2,032 offences recorded in 2019, up 13 percent on the previous year, according to government figures.
A German court in December handed down a life sentence to the assailant behind a deadly far-right attack last year that nearly became the country’s worst anti-Semitic atrocity since World War II.
After failing to storm a synagogue, the gunman shot dead a female passer-by and a man at a kebab shop.