Following an attack on a German member of the European Parliament and a Green Party election worker in the city of Dresden, police have identified all four suspects.
A 17-year-old had previously turned himself in to police on Sunday following the attack on Matthias Ecke, who represents the Social Democrats (SPD) in the European Parliament, during campaign work on Friday evening.
Evidence was seized during house searches and is now being analysed.
The suspects are four young men, aged 17 and 18. As there are no grounds for arrest, they are at large, according to the public prosecutor's office.
The motive for the offence is currently under investigation. It will take some time before the investigation is finalized, the statement by the police and the state's public prosecutor's office said.
Ecke was brutally beaten by four assailants on Friday evening while hanging campaign posters in the eastern German city.
He is still in hospital where he underwent surgery on Sunday.
Witnesses described the assailants as dressed in dark clothing and said they seemed to be part of the far-right extremist scene.
Ecke is the SPD's top candidate in the state of Saxony for June's European elections. He has served in the European Parliament since 2022.
Minutes before Ecke was attacked, according to the police, a group of four assailants had also assaulted a 28-year-old Green Party campaign worker while he was putting up posters in the same part of Dresden.
The attacks triggered a debate about the escalation of violence during election campaigns.
Several thousand people demonstrated to denounce the attacks and defend Germany's democratic values in Dresden and Berlin on Sunday.
Defence Minister Boris Pistorius has described the recent attacks on politicians as a major threat to democracy itself.
"If local politicians - and this applies equally to members of state parliaments, the German Bundestag and the European Parliament - no longer dare to run for office, no longer dare to put up posters or attend election rallies, (...) then democracy is dying from the ground up," Pistorius said on Monday.
Nothing worse could happen to democracy, the minister added.
"We will not leave this democracy, our way of living in freedom and security, to fascists, right-wing extremists or those who do this business for others on the streets as the extended arm of the AfD," he said, referring to the far-right Alternative for Germany (AfD) party.
He said the attacks on Friday are reminiscent of Nazi Storm Troopers "beating people on the streets before 1933." Parts of the AfD are right-wing extremist, he added, "and that is how we must finally treat them."
