Last Updated Jan 31, 2015 11:43 PM EST
Bobbi Kristina Brown, daughter of the late singer Whitney Houston, was in a medically induced coma Saturday night after being found unresponsive in a bathtub at her home outside Atlanta, CBS affiliate WGCL-TV reported.
Police in Roswell, Georgia, said Brown's husband, Nick Gordon, and a friend found her face-down in the tub and started CPR.
When police officers arrived on the scene in response to a 911 call at 10:25 a.m., they started life-saving measures until emergency medical services personnel arrived and transported Brown to North Fulton Hospital in Roswell.
"She's still breathing; she is alive," Officer Lisa Holland, a police spokeswoman, told CBS Radio News. Holland had no other information on Brown's condition.
According to WGCL, police executed a search warrant for Brown's home but would not elaborate on the reason. So far, they had found nothing to indicate whether drugs or alcohol were a factor, the station said. It was unclear whether Gordon or anyone else was home when Brown became unresponsive.
"We are interviewing all the family members and friends that were at the house at the time," Holland told CBS Radio News. "...We don't know that if it was an accident or what this could be."
Police were called to the home Jan. 23 for a report of a fight, Holland said. When officers arrived, they found no one there.
Brown, 21, is the daughter of Houston and R&B singer Bobby Brown. A representative for the family did not immediately return messages seeking comment.
A confidential source who had been at the hospital with the family most of the day told WGCL Brown was being treated in the intensive care unit where doctors have stabilized her breathing. The source said Brown's father was making his way to the hospital and that while Brown was unconscious, the mood was positive.
Just after midnight Saturday morning, Brown posted two photos of herself to Instagram.
Houston was found dead in a hotel bathtub on Feb. 11, 2012, in Beverly Hills, California. The 48-year-old singer had struggled for years with cocaine, marijuana and pills, and her behavior had become erratic.
Authorities examining Houston's death found a dozen prescription drug bottles in the hotel suite. They concluded that Houston accidentally drowned. Heart disease and cocaine use were listed as contributing factors in Houston's death.
Over her career, Houston sold more than 50 million records in the United States alone. Her voice, an ideal blend of power, grace and beauty, made classics out of songs like "Saving All My Love For You," ''I Will Always Love You," ''The Greatest Love of All" and "I'm Every Woman." Her six Grammys were only a fraction of her many awards.
Houston had her first No. 1 hit by the time she was 22, followed by a flurry of No. 1 songs and multiplatinum records.
Houston left her entire estate to her daughter.