The two men, aged 25 and 27, were found with serious injuries in central Norrköping in the early hours of Thursday.
One was discovered lying outside a bar on Prästgatan and the other was found in the vicinity of an indoor car park nearby on Repslagargatan, said authorities.
Initial witness statements claimed the men had been hurt with a knife. However police later confirmed it was believed they had only been injured with a sharp weapon, which had not been found by 9am.
“They have been injured with some kind of tool. What that is, we don't really know yet,” police press spokesperson Fredrik Kliman told the TT newswire earlier on Thursday morning.
Ung man död efter misstänkt knivattack i natt – en svårt skadad https://t.co/tbxlh1InA2 pic.twitter.com/3Vi8hhSOsI
— Aftonbladet (@Aftonbladet) November 26, 2015
The streets around the scene were cordoned off during the night while forensic teams investigated. Meanwhile, police were appealing for more witnesses to come forward.
“We think that more people were moving in this area at around 1am tonight,” said Kliman.
The men were taken to hospital by ambulance, where they underwent emergency surgery. However, the 25-year-old died a few hours later, according to police. The 27-year-old was left with life-threatening injuries.
Kliman confirmed the pair had been identified, but declined to comment on whether or not they were known to police.
“It is too early to talk about that,” he said.
It was not immediately clear if the men had been injured fighting each other or if a third assailant had been involved.
Two months ago, four people, including two security guards, were stabbed in two bar brawls in central Norrköping.
And in August a man stabbed three people in the town in what appeared to be a random attack.