A 41-year-old Alhambra woman has been arrested in the death in March of a newborn girl whose body was found in a ravine alongside railroad tracks in the San Gabriel Valley community, authorities announced Thursday.
Tonya Mae Schaefer was arrested on suspicion of homicide and child cruelty and jailed in lieu of $1-million bail.
Alhambra police said they expected the Los Angeles County district attorney's office to file charges today.
The death of the infant -- whose body was discovered by railroad workers inspecting the tracks -- so shocked residents that hundreds turned out for a candlelight vigil and for a funeral Mass held at St. Therese Catholic Church. Church members named the unidentified baby Therese Rose.
The Los Angeles County Board of Supervisors in May announced a $10,000 reward for information leading to an arrest.
Capt. Robert Panza, who heads the city Police Department's detective division, said that more than 50 tips came in from the public, most of them shortly after the discovery of the baby March 12.
Authorities said one of those tipsters, whom they declined to identify and who might be eligible for the reward, led investigators to focus on Schaefer.
DNA tests, they said, revealed that Schaefer was the baby's mother.
Panza said police did not know how the tipster, who will be questioned further but is not considered a suspect in the case, learned that Schaefer could have been the mother.
Police, who had interviewed Schaefer earlier in the eight-month investigation, brought her back Thursday for further questioning and placed her under arrest.
"Our investigators took this personally," said Alhambra Police Chief Jim Hudson. He said the lead investigator, Det. Kevin Laing, "worked almost exclusively on this case" for the last eight months.
"This had a profound impact on the community as a whole," Hudson said. "I hope this provides closure for them, and for us as well."