A Swedish policeman was stabbed in a bustling Stockholm square on Thursday, police said, indicating that a man had been arrested in connection with the attack.
"A police officer has been stabbed in the back and the neck," inspector Ronnie Tellberger told AFP, saying the assailant had attacked him from behind.
The motive for the attack was not immediately clear.
Sweden has been on edge since April when an Uzbek asylum seeker deliberately ploughed a truck into shoppers in central Stockholm, killing five people including an 11-year-old girl.
The incident occurred around 10:30 am (0830 GMT) near a subway exit in Medborgarplatsen Square in the Sodermalm neighborhood.
"A preliminary enquiry has been opened into attempted murder," Stockholm police said in a statement.
The police officer was taken to hospital, but his life was not in danger, it said.
Another police officer arrested the suspect. Police were investigating the incident as attempted murder, DPA said.
Several police patrols were dispatched to the scene at Bjorns Tradgard, a little park just off the square Medborgarplatsen, located in the district of Sodermalm, a trendy section of the capital.
Police later said the police officer's injuries were not life-threatening.