PLEASANTON (CBS SF) - A 13-year-old girl and her 37-year-old mother who were found shot to death in their Pleasanton home Monday evening were both shot once in the head, police said.

Pleasanton police responding to a 911 call around 6 p.m. Monday found Amy Freeman Burton dead in her home at 3532 Stacey Court. Freeman's daughter, Ainsley Freeman, was found shot nearby and was transported to Eden Medical Center, where she later died.

Initial results from autopsies conducted by the Alameda County coroner's bureau Wednesday suggest that Ainsley did not likely shoot herself, police said.

Freeman's autopsy did not provide clear evidence of a self-inflicted wound, but police said that scenario has not been eliminated.

Bullets recovered from Freeman and Ainsley match those found in a handgun located near the mother and daughter.

Police said pending lab results, which are not expected to be available until sometime next week, will indicate whether that weapon was involved in the deaths.

Anyone with information about the deaths is asked to contact Pleasanton police at (925) 931-5100.

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