The man, who is in his 20s, received cuts to his hands after he was set upon by the “killer clown” assailants in the town of Falköping, 120km northeast of Gothenburg.
“We have information about three perpetrators, two stripy and one spotty,” Emma Ekdahl from the local police told Swedish Radio.
According to Expressen newspaper, the man was surrounded by the three clowns at around 6am on Sunday morning. The attack has been classified as an assault.
Jenny Widén, a local police spokesman, said that details of the attack remained hazy.
“The man’s hand was wounded. I don’t know how it happened, and I see no mention that he needed to be taken to hospital,” she told the newspaper.
“We have discussed clowns a lot. They are frightening, not least because there are many children who are extremely afraid,” Widén added.
Worried citizens in the town have started a Facebook group to coordinate clown spottings in an attempt to help citizens affected by the new menace.
“The aim is not to hurt any clowns. The aim is to keep track of them to make it easier for those who are afraid,” William Player, the local reggae artist who started the group, told the Swedish radio.
The site gives citizens instructions for what to do if they encounter a clown.
“Firstly and most importantly, ring the police!” it advises. “Do not attempt to attack the clowns yourself.”
It also asks for volunteers willing to join night patrols to protect people from the clowns.
Clown-hunting citizen watch Facebook groups are now being set up across Sweden, led by Clown Hunters Sweden.
On Saturday evening an eight-year-old boy was frightened at home by a clown in Skövde, a town near Falköping.
There was a knock on the door, and he opened it, believing it was his mother returning.
“But it was not his mother, it was a clown,” Emma Ekdahl told Swedish Radio. “He became frightened, so frightened that he jumped out of the window.”
Police in Sweden have yet to arrest and unmask the identity of one of the clowns.