Police had been called to the elderly couple’s flat on Wednesday just before 9am by neighbours who had overheard what they thought was some sort of brawl.

They arrived to find the elderly couple dead.

The two victims so seriously savaged by stabbing wounds that there was no question of the cause of death, police told the Aftonbladet newspaper.

No one else was present in the flat at the time of the police’s arrival and it is believed that the perpetrator fled by way of the balcony, dropping down two storeys.

Witness reports stated that a man, wearing a chequered shirt, carrying a bag, and with blood on his clothes, was spotted running from the scene among the houses.

Late on Wednesday evening a man was apprehended not far from the apartment and brought in for questioning. He was later arrested on suspicion of the murder of the elderly couple.

On Thursday the TT news agency reported that the suspect who was apprehended late on Wednesday was the murdered man’s 41-year-old son.

He reportedly has a history of violence, having been convicted of killing his mother in 1997 and being sentenced to time in a secure psychiatric facility.

According to the minutes of the trial, the now murdered father said that his relationship with the son was “strained” and that he was often very aggressive.

A few weeks before his mother’s death in 1996, he had called her up and said that he would “hack her to death”.

She was found stabbed to death in her Tullinge flat shortly after.

After his release, the 41-year-old has repeatedly been convicted for theft.

He was most recently released from jail on New Year’s Eve and has lacked a permanent address since then.

”He has been arrested and will receive legal counsel. That is all I want to say,” said Åsa Johanneson of the police to the paper.

According to Aftonbladet, there is no known motive for the killing of the couple.

”No, not that I know of. But the forensic investigation has just been concluded,” said Åhlin to the paper.