Gerwald Claus-Brunner had allegedly also transported the victim's corpse across Berlin. Both men's bodies were found in the politician's apartment on Monday night.
Shocking new details continue to emerge about the suspected murder by the Berlin Pirate Party politician, Gerwald Claus-Brunner.
German newspaper "Die Welt" reported on Thursday that Claus-Brunner confessed to the murder in a letter to a Pirate Party colleague.
The unconfirmed report could put pressure on the Pirate party; on Monday, when news broke of Claus-Brunner's suicide, the Pirates suggested that the 44-year-old was suffering an "incurable illness."
According to the German newspaper "Bild," the police are investigating whether Brunner had an accomplice, or at least someone who knew of the murder. Police would not confirm the existence of a letter, but said that they were adjusting the investigation.
The Chair of the Pirate Party's Berlin faction, Bruno Kramm, retreated to his second home in Finland. "I need some distance," he told dpa. "I just want this whole ordeal to end."
He also said he would assess how he and the Berlin wing of the party would continue their political work.
Victim's body transported through Berlin
Claus-Brunner is believed to have committed the murder in the victim's apartment in the Berlin borough of Wedding - around 11 kilometers (7 miles) from Brunner's apartment in Steglitz, where both men's bodies were found.
Police confirmed that they had found traces of blood in the victim's flat.
German newspaper reports claim that Claus-Brunner carried the body through Berlin last week. Berlin police did not confirm this, spokesman Martin Steltner merely said, "The corpse had to be transported - one way or another."
The exact day of the murder is still unconfirmed. The victim's autopsy report allegedly suggests that he was killed a few days before Claus-Brunner took his own life.
A neighbor of Brunner's reported that she heard something heavy being carried and dragged across the floor on September 15, a Thursday night.
A difficult relationship between the victim and perpetrator
Fresh details have also come to light regarding the turbulent relationship between the two men.
Claus-Brunner posted the following tweet about the victim on or close to the day he is suspected of killing of him:
"My love, my life, for you my dear fuzzy head, for ever and ever!"
The victim, a 29-year-old man identified as Jan L., had reported Brunner to the police in June, accusing him of stalking.
However, the state of their relationship since the accusation remains unknown.
Jan L. had been a dedicated follower of the Pirate Party and had worked in Claus-Brunner's party offices.
Claus-Brunner had told an acquaintance that "something had unfortunately happened" between them. Friends and party colleagues revealed that Jan L. did not return the love that Claus-Brunner felt for him.
However, Claus-Brunner allegedly refused to let go, continuing to call Jan L. by his nickname Wuschelkopf.
The Leipzig Pirate representative Ute Gabelmann reportedly assumed that the men were still a couple. In her obituary for Claus-Brunner, she even wrote that Jan L. had distracted him from his work in the assembly.
Bodies found on Monday
Clause-Brunner and Jan L.'s bodies were discovered in the Pirate politician's apartment on Monday night.
Reports initially suspected that both men had committed suicide. However, police announced the following day that Claus-Brunner had possibly killed Jan L., who was found naked with multiple injuries, before taking his own life.