The dog ran for some distance before dropping the 6-month-old baby, who was helicoptered to the Los Angeles County-USC Medical Center for treatment of bite injuries to the chest, Monrovia police Lt. Michael Lee told the Pasadena Star-News.
"It snatched up the child in its mouth and took off," said Lee. "He didn't grab the child and shake it, but he bit onto her hard enough to cause significant injuries. ... Because of that and the age of the child, she is listed in guarded condition."
Shortly before 2:30 p.m. Monday, the mother had gone next door to visit a neighbor.
She was standing at the neighbor's door, with her daughter on her right shoulder, when the 3-year-old, 170-pound Great Dane snatched the baby in its mouth and ran down the street, police said.
The dog, which had no record of aggressive behavior, was being held in quarantine as police investigate.