An attacker hit a former mayor of Berlin in the head with a bag in the latest in a rash of assaults against politicians in Germany, police said Wednesday.

The suspect came up behind Franziska Giffey to slug her in the head and neck at a library on Tuesday afternoon before running away, police said in a statement.

Giffey, who is now Berlin state's economy minister and a member of Chancellor Olaf Scholz's Social Democratic Party (SPD), was treated in hospital for light injuries.

Berlin's current mayor Kai Wegner condemned the assault, saying anyone who attacks politicians are "attacking our democracy".

"We will not tolerate this," he said, vowing to examine "tougher sentences for attacks against politicians".

A European parliament lawmaker, also of the SPD, was seriously injured by four attackers last week as he put up EU election posters in the eastern city of Dresden.

Matthias Ecke, 41, needed an operation for serious injuries sustained in the attack, which was denounced by Scholz as a threat to democracy.

Dresden has been a hotspot for assaults against politicians, with a new case reported again on Tuesday.

A politician, identified by police only as a 47-year-old from the Green party, was threatened and spat on.

The politician was putting up campaign posters for the European elections when a man came up, pushed her to the side and tore down two posters.

The man insulted and threatened the politician, while a woman joined in and spat on the victim, police said.

Both suspects were arrested, police said, identifying them as a 34-year-old German man and a 24-year-old woman.

Both were in a group who were standing at the area and who had begun making the banned Hitler salute when the politician began hanging up posters.

According to provisional police figures, 2,790 crimes were committed against politicians in Germany in 2023, up from 1,806 the previous year, but fewer than the 2,840 recorded in 2021, when legislative elections took place.