A San Mateo woman allegedly killed her neighbor Saturday by repeatedly hitting her on the head with an aluminum child-sized baseball bat, police said.
The pair's neighbor Rose Johnson said the suspect -- 40-year-old Brenda Martinez -- and the still unidentified 66-year-old woman were friends for many years. However, they had a falling out about money roughly six months ago and stopped talking to each other, she added.
According to police, Martinez went to the San Mateo Police Department at 8:30 p.m. Saturday and approached officers in the front lobby. A department statement indicated that she not only "alerted officers" but also "implicated herself as a suspect" in the homicide.
Officers responded to a residence on the first block of N. Claremont St. where they found the victim. She was unresponsive, having experienced "obvious head trauma," and was pronounced dead at the scene, police added.
For her part, Johnson described Martinez as "very violent" and "very verbal" while the victim was "light-hearted," "sweet" and never spoke badly of anyone.
"I just sat down and couldn't believe a murder happened here," Johnson said.
Police are currently investigating a motive. Meanwhie, Martinez is in San Mateo County Jail and is scheduled to be arraigned Tuesday.