Berkeley police are asking for the public's help in finding a 5-year-old girl, who they say was taken by her mother, who has diminished capacity.
Police said Mayalyia Booker was last seen with her mother, 34-year-old Laquita Davis, in the 1500 block of Prince Street at 3:14 p.m. Friday.
The girl was visiting her grandmother on Prince Street when Davis picked her up unexpectedly, police said, adding the father has custody of the child.
Davis, who is homeless, does not have any visitation rights, police said.
"Our hearts go out to the child," said Randy Files with the Berkeley Police Department. "We just want to make sure the child is where (she) is supposed to be and no one is harmed."
Berkeley police are working with the Alameda County Sheriff's Office, who brought in a K-9 unit to help with the search. The K-9 unit tracked the mother and child to the Ashby BART station in Berkeley, which is about 10 minutes away from the spot where Davis took Mayalyia.
Police believe the pair could be in Oakland.
Berkeley police have not issued an Amber Alert because they do not think Mayalyia is in danger.
The child's grandmother says Davis has taken away the toddler once before, but brought her back. Officers are unsure when that happened and how long the woman kept her daughter with her.
Mayalyia is described by police as being between 3-foot-6 and 4-feet tall with a thin build, brown hair and brown eyes.
Police say Mayalyia has short hair in twists and was wearing a black shirt, black pants and gray tennis shoes.
Davis is described as 5-foot 8-inches tall, weighing 172 pounds, with brown hair and brown eyes, and has two braids and was last seen wearing a black jacket and blue jeans.
Police departments around the Bay Area are on the lookout for Davis and Mayalyia as are BART police officers.
Berkeley police say people who have information that can help in safely locating Mayalyia Booker should call 911 or contact them at 510-981-5900.
NBC Bay Area's Jean Elle contributed to this report.