A 22-year-old female employee was killed on Monday in a stabbing at a shelter in western Sweden for unaccompanied minors seeking asylum, according to the police.
The woman died of her injuries in hospital, police said.
A male suspect has been arrested on suspicion of murder or manslaughgter, but police did not give any information on his age or nationality, nor did they have details on what might have triggered the attack.
Police also questioned other witnesses at the accommodation in Molndal, near the west coast city of Gothenburg.
The youths living at the shelter are aged 14 to 19. Some have been granted asylum while others are waiting for their bids to be assessed.
The Swedish Migration Agency said that the number of reported threats or acts of violence at refugee centres in the country more than doubled to 322 incidents between 2014 and 2015.
The figures include both altercations between asylum seekers and staff, or between asylum seekers.
Last year, Sweden registered a record 163,000 asylum bids, twice that of 2014. Close to 35,400 bids were made by unaccompanied minors, the majority of whom were Afghans.