Police received a call at about 7:40 a.m. reporting a possible deceased person inside a home in the 1400 block of Park Glen Court, Concord police Lt. Jim Lardieri said.
When they arrived, officers found a 10-year-old girl who told them that her mother was dead inside their residence.
Officers entered the home and found Liu in a bedroom. She was pronounced dead at the scene, Lardieri said.
The girl told officers that her mother had woken her up and assaulted her with a knife, Lardieri said. The girl struggled with her mother and was able to break free, he said.
Her mother then appears to have killed herself with the knife and the girl called 911.
An autopsy was being conducted on Liu's body this morning, a deputy coroner said.
Nobody else was home at the time of the attack.
The girl was taken to a hospital and was listed in serious but stable condition, Lardieri said. She remained in the hospital today.
Police this morning were not releasing further information about what may have led to the attack.