Prathaan/iStock(LOS ANGELES) — A mother and her 17-year-old daughter were strangled to death in Southern California, officials said, as authorities search for their suspected killer.

Cecilia Meza, 41, and her daughter Kelsey Meza, 17, were found dead in a Monrovia home on Dec. 5 by officers conducting a welfare check, the Los Angeles County Sheriff’s Department said.

Cecilia Meza died from strangulation while Kelsey Meza died from blunt head trauma and strangulation, according to the Los Angeles County Medical Examiner’s office.

Their suspected killer, Nimrod Perez Guerrero, remains at-large, the sheriff’s office said.

Kelsey attended Monrovia High School, across the street from her home, reported KABC.

The 17-year-old was “excited about going to college,” and was a “sweet, kind girl who always went out of her way to help others,” Monrovia Unified School District Superintendent Katherine Thorossian said in a Dec. 6 statement.

“It is not natural for us to comprehend unnatural death – especially one in our own back yard,” Thorossian said. “We’ve deployed our emergency response team, including trained counselors and psychologists, to Monrovia High School, where they will remain as long as they are needed to support students and staff coming to terms with their shock and grief.”

Guerrero was believed to have known the victims, ABC Los Angeles station KABC reported.

The sheriff’s office did not immediately respond to ABC News’ request for comment.

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