Stephan E. is accused of murdering a member of Chancellor Angela Merkel's CDU party in central Germany. Prosecutors also suspect he was involved in a stabbing attack on an Iraqi refugee in 2016.
Police in the central German state of Hesse are investigating whether a right-wing extremist suspected of murdering a local politician was also involved in the unsolved stabbing of an asylum-seeker more than three years earlier.
State prosecutors in the city of Kassel said on Friday that Stephan E. was under suspicion of stabbing a 22-year-old Iraqi refugee in January 2016. The perpetrator critically injured the man before fleeing the scene.
Police searched Stephan E.'s home on Thursday as part of the investigation.
Stephen E. was arrested in June on suspicion of shooting Walter Lübcke, the head of the Kassel regional government, earlier that month.
The 45-year-old initially confessed to killing Lübcke over his pro-migrant views, but retracted the confession shortly thereafter.
Before his killing, Lübcke reportedly received death threats for favoring Merkel's open migration policy.
amp/jm (epd, dpa)