(CNN) Two people were arrested on Thursday morning over the murder of pro-migrant mayor Walter Lübcke, according to Germany's federal prosecutor, just days after a suspect already in custody confessed to the killing.
A spokeswoman for the prosecutor, Kerstin Wacker, told CNN that the two alleged perpetrators will be questioned by the judge leading the investigation.
Lübcke, 65, was shot in the head at close range on the terrace of his home in the small village of Istha, in central Germany, in the early hours of June 2.
A German security source told CNN earlier that a far-right supporter, identified only as Stephan E., confessed to Lübcke's killing on Tuesday.
The source added that Stephan E. said he killed Lübcke because of the politician's views, in particular his liberal position on migration and refugee policies.
The 45-year-old man was arrested shortly after the killing based on traces of DNA evidence from the crime scene, according to the Hesse state office of criminal investigation and Kassel's public prosecutor.
Police have previously said the suspect had a long criminal record and had "openly expressed opinions and public views" that linked him with the far right.
Lübcke was a member of Chancellor Angela Merkel's ruling Christian Democrats and an outspoken supporter of the government's pro-migrant policies in the wake of the 2015 refugee crisis. The 65-year-old politician was the president of the Kassel regional council in central Germany.
According to the police, Lübcke first received death threats after a YouTube video emerged of him defending the country's immigration policies at a public meeting in Kassel in October 2015.
The meeting was also attended by members of Pegida, a far-right anti-Islam movement.
In the video, Lübcke says: ''You have to stand up for your values. If you don't share those values, then anyone is free to leave this country if they don't agree." Some members of the crowd could be heard shouting "get out, get out" in response.
Merkel opened Germany's doors to more than 1 million migrants in 2015. But her policy, hailed by humanitarians, also attracted fierce criticism from the right, particularly following a number of terrorist attacks across the country in summer 2016.