Update: The 12-year-old girl has now been upgraded from critical to stable condition, according to Sgt. Glen Coleman of the Monrovia Police Department. Coleman said the police received a call from the girl's father regarding the upgrade.
"The dad said she's responding well to the doctors," Coleman said.
Originally: An unidentified woman was arrested for allegedly of the collision, police announced Friday night.
The suspect was identified as Emma Tapia-Gonzalez, 23, of Duarte, Lt. Zeke Cereceres.
The victim remains in critical condition and is in surgery, according to a news release from the police.
Witnesses provided a description of the vehicle and a partial license plate number to police, which led police to an address in Duarte, Cereceres said.
"Officers went to the location and eventually found the car and made contact with the driver," Cereceres said.
Tapia-Gonzalez was on her way to visit someone and had a passenger in the car when the alleged hit and run occurred, Cereceres said. She was booked on felony hit and run charges, according to police.
The girl was hit while crossing the street shortly before 4 p.m. at the intersection of Canyon Boulevard and Huntington Drive.