Three children whose bodies were found in a suburban Minneapolis lake over the holiday weekend died in drownings that were classified as homicides, and their mother died of a drowning that was suicide, authorities said Tuesday as they also identified the victims.

Searchers recovered the bodies of Molly Cheng and her three children, ages 3, 4 and 5, from Vadnais Lake on Friday and Saturday. Authorities had said earlier the deaths were being investigated as a triple murder-suicide.

The Ramsey County Sheriff's Department said Tuesday that Cheng called police on Friday morning and said her husband, Yee Lee, had fatally shot himself. Maplewood police say they arranged for social workers to assist Cheng and her children, CBS Minnesota reported.

That afternoon, one of Cheng's relatives called police to say she planned to kill her children and herself, the department said.

Maplewood police issued a statewide alert to "attempt to locate and check the welfare" of Cheng and her children, CBS Minnesota reported. Law enforcement agencies were able to track Cheng's cell phone, placing her in the area of Vadnais-Sucker Lake Park around 5:45 p.m.

Deputies located several pairs of kids' shoes and vehicle keys on the east shore of the lake.

The Ramsey County medical examiner determined that the cause of 4-year-old Quadrillion Lee and 3-year-old Estella Zoo Siab Lee's deaths was drowning and smothering. Five-year-old Phoenix Lee's death was caused by drowning.

If you or someone you know is in emotional distress or suicidal crisis, call the National Suicide Prevention Hotline at 1-800-273-TALK (8255).

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