Police Say Minnesota Mom Smothered 2 of 3 Kids She Murdered Before Killing Herself

Molly Cheng, 23, killed her children hours after she reported that her husband had fatally shot himself in their Maplewood, Minnesota, home on July 1

Police in Minnesota have revealed grim new details about the July 1 deaths of three children at the hands of their mother.

Molly Cheng smothered and drowned two of her children, then drowned the third child before ending her own life by drowning herself, police said.

Cheng, 23, killed her children — Quadrillion T. Lee, 4, Phoenix Lee, 5, and 3-year-old Estella Zoo Siab Lee — hours after she reported that her 27-year-old husband Yee Lee had fatally shot himself in their Maplewood, Minnesota, home on July 1.

The Ramsey County Sheriff's Office said Quadrillion and Estella died by drowning and smothering and that Phoenix died by drowning. Their deaths were ruled homicides.

Police said Cheng died by suicide by drowning.

Molly Cheng. Facebook

The sheriff is investigating the death of Cheng and her children as a triple-murder suicide.

"Our hearts go out to the family, friends, and community impacted by this terrible tragedy," Ramsey County Undersheriff Mike Martin said in a statement. "The sheriff's office is continuing to investigate the circumstances of this incident to provide clarity and closure to the surviving family members."

Cheng contacted police on July 1 at approximately 10:30 a.m. to report that her husband had shot himself. Deputies responded to the Rolling Hills Estates Mobile Home Park and found Lee dead from a gunshot wound.

The medical examiner ruled his death a suicide.

Facebook

Later that afternoon, around 4 p.m., Cheng's relative called 911 "stating that Molly was going to kill her children and herself," according to a police press release.

Police in Maplewood issued a statewide alert to find Cheng and her children. At 5:45 p.m. investigators tracked Cheng's cell phone to the area of Vadnais-Sucker Lake Park in Vadnais Heights.

Soon afterward, deputies found her car in the parking lot of the park. They then discovered several pairs of kids' shoes and her car keys on the east shore of the lake.

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Deputies pulled Quadrillion from Vadnais Lake around 7:30 p.m. and began life-saving measures. He was declared dead by medics.

Phoenix was found in the lake at 12:03 a.m. on July 2.

Cheng's body was found in the lake around 10:39 a.m. Estella was discovered about 20 minutes later.

If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text "STRENGTH" to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.