BERLIN－Senior German officials on Sunday condemned attempts by far-right protesters and others to storm the parliament building following a protest against the country's pandemic restrictions.

Hundreds of people, some waving the flag of the German Reich of 1871-1918 and other far-right banners, breached a security barrier outside the Reichstag late on Saturday but were intercepted by police and forcibly removed.

"Reich flags and right-wing extremist provocations in front of the German Bundestag are an unbearable attack on the heart of our democracy," German President Frank-Walter Steinmeier said on Sunday. "We will never accept this."

Steinmeier said people had the right to express their anger about the coronavirus restrictions and to question them publicly, including with demonstrations.

"My sympathy ends where protesters allow themselves to be used by enemies of democracy and political agitators," he said.

Police used pepper spray to drive back the protesters, who earlier in the day had participated in a large rally through the capital.

About 300 people were arrested in front of the Reichstag and following an incident at the Russian embassy, according to police.

Berlin's top security official, Andreas Geisel, praised three officers who had stood alone against the protesters outside the Reichstag until reinforcements arrived. Opposition parties criticized the police's failure to station sufficient officers around the parliament, despite public warnings from far-right extremists that they planned to try to enter the building.

Robert Habeck, the co-leader of Germany's Green party, called for a thorough investigation into the incident.

The head of Chancellor Angela Merkel's center-right party, Annegret Kramp-Karrenbauer, expressed anger at the incident.

"That the Reich flag should fly again at the German Bundestag is intolerable," she said.