Several thousand people rallied in support of Israel in Berlin on Sunday as the German Chancellor Olaf Scholz vowed to stamp out a resurgence of anti-Semitic incidents in the wake of the Israel-Hamas conflict.

Police said around 10,000 people gathered at Brandenburg Gate for the demonstration in solidarity with Israel and in opposition to anti-Semitism, though organisers put the figure at 25,000.

"It is unbearable that Jews are living in fear again today -- especially in our country," Germany's President Frank-Walter Steinmeier told the crowds.

"Every single attack on Jews, on Jewish institutions, is a disgrace for Germany. Every single attack fills me with shame and anger," he said.

Earlier in the day, Chancellor Olaf Scholz expressed a similar message at the opening of a new synagogue in the city of Dessau.

"There must be zero tolerance for anti-Semitism in Germany," Scholz said.

Germany will "defend and protect" Jewish life, he added, voicing his shock at anti-Semitism spreading "around the world and, shamefully, also here in Germany".

- Molotov cocktails -

Germany has seen a spate of anti-Semitic incidents in the wake of the October 7 attacks by Hamas on Israel and Israel's retaliatory bombing campaign.

Some Jewish homes in Berlin have been marked with the Star of David and attackers last week hurled two Molotov cocktails at a Jewish synagogue in the city.

There must be no turning a blind eye "when Jews are not safe on Germany's streets, when Stars of David are smeared on homes, when firebombs are thrown at synagogues", Scholz said.

The opening of the synagogue in Dessau came 85 years after a synagogue in the city was destroyed in the "Kristallnacht" anti-Jewish pogrom on November 9, 1938, when Nazi mobs torched and ransacked synagogues and Jewish-owned businesses across Germany -- widely seen as the start of the Third Reich's drive to wipe out Jews.

The new building has been named the Weill Synagogue after the German-American composer Kurt Weill, whose father was a cantor in Dessau's Jewish community.

Dessau is just 50 kilometres (30 miles) from Halle, where a gunman killed two people after failing to storm a synagogue on Yom Kippur in October 2019.

Germany has the third-largest Jewish community in Europe, according to the interior ministry.

The Central Council of Jews in Germany puts the number of practising Jews in the country at around 100,000 and the number of synagogues at around 100.

- Painful memories -

Anti-Semitic acts have increased sharply in the country amid the latest turmoil in the Middle East, according to the Federal Association of Research and Information Centres on Anti-Semitism (RIAS).

In the period from October 7 to 15, RIAS documented 202 anti-Semitic "incidents" compared with just 59 during the same week in 2022.

Sigmount Koenigsberg, a pointman on anti-Semitism for the city's Jewish community, told the Rheinische Post newspaper on Sunday that the rise anti-Jewish incidents brought back painful memories of Nazi Germany.

"It is the first time since Nazi rule that this is happening again in Germany. It reminds my community very much of that terrible time," he said.

Susanne Liebegott, a 60-year-old teacher, said she attended the rally in Berlin because "it is important for me to stand against anti-Semitism".

"I'm not necessarily pro-Israel and don't really take a stand. But the anti-Semitism in Germany, which is also on the rise, worries me a lot," she told AFP.

Carsten Remmers, 41, a music business manager at the demo with his four-year-old daughter, said it was "enormously important to say that we stand by Israel".

"Especially we as Germans have a special responsibility," he said.

Germany has seen several large rallies in support of both Israel and the Palestinians since October 7.

A planned pro-Palestinian demonstration near the Brandenburg Gate on Sunday was banned due to fears of anti-Semitism and violence.