“At the moment, it’s being treated as murder with an alternative charge of manslaughter,” police spokesperson Lars Liewenborg told the TT news agency.
Police arrived at the address, located in the Arnö suburb of Nyköping, about 100 kilometres south of Stockholm, to find a dead infant and a 29-year-old woman with severe knife wounds.
According to the Aftonbladet newspaper, police suspect the woman’s wounds were self-inflicted.
“She is seriously injured, but the wounds aren’t life threatening,” said Liewenborg.
A call about the incident came shortly before 11am on Thursday, and police are calling the incident a family tragedy which has left neighbours and nearby residents in the quiet suburb shaken.
The woman was first taken to a local hospital before being transported to Karolinska University Hospital near Stockholm.
The 29-year-old mother is suspected of killing the infant, but hasn’t been informed of the suspicions as she was unable to be interviewed by police as of Thursday afternoon.
A formal decision to detain the woman hasn’t been taken either and she remains under observation at the hospital.
Police have however spoken with other family members who are said to have been in the house when the baby died.
But it remains unclear if they saw exactly what happened.
“We know more or less what has happened, but we’re not going out with that,” said Liewenborg.