Police are now investigating whether the Moroccan was raped on Sunday in the Ottakring district, as he claims, and if the Syrian man was involved.
The Moroccan is in police custody and the 27-year-old Syrian is in hospital, where he's being treated for serious injuries.
Both men are asylum seekers who live in accommodation in the Favoriten area. Originally, the 45-year-old told the authorities he was 35 years old and came from Syria. Police spokesman Thomas Keiblinger said it was likely he had lied as he thought he'd have a better chance at being granted asylum if he was believed to be from war-torn Syria.
Keiblinger said the man had refused to go into much detail about his rape ordeal, saying he would save his story for the judge.
He was treated in hospital on Sunday lunchtime for injuries that suggested he had been assaulted. He told doctors he had been raped by two men in Ottakring.
He said he had gone with them to an apartment where they had offered him a glass of lemonade, and shortly after drinking it he began to feel unwell and lost consciousness. He says that this is when the two men raped him.
When he woke up he was in pain and went to a hospital, where doctors contacted the police after hearing his story.
After being released from hospital he went back to his accommodation in Favoriten, and 12 hours later stabbed the Syrian man with a pocket knife in the chest. Witnesses said the men had not fought before the attack, and that the Moroccan had not said anything prior to the stabbing.
Keiblinger said the Syrian had been able to talk to police from his hospital bed, but that he claimed he had no idea why the Moroccan had attacked him and he denied having raped the man.
The Moroccan man's blood will be tested to see if he was given a date rape drug and police are trying to locate the apartment where he said the assault took place. Other asylum seekers who live in the Favoriten home told police that they believe he has psychological problems.