Calgary police say a woman's death Sunday in Mission is "suspicious."

Officers were called to a residence around 12:30 p.m. MT in the 200 block of Holy Cross Lane S.W. for reports of a woman in distress, police said. When they arrived, they discovered a woman in her 40s dead inside the residence.

Investigators say they have not determined a cause of death but do have a person of interest in custody.

Police say the victim and the male in custody knew each other but their exact relationship is not clear at this point.

This is not considered a random incident.

Police won't say whether the person of interest was brought in to custody from the residence or from nearby.

An autopsy is scheduled for Monday.