Robert Anderson Cotton is facing two counts of murder with an allegation of using a knife as a deadly and dangerous weapon, according to the D.A.’s Office.
On March 22, Cotton allegedly stabbed his mother Carol Brown, 67, and his uncle Kenneth Preston, 69, at the house they shared in Southern California. One of Brown’s work colleagues witnessed the attacks while on a Zoom call with her.
“This is a horrific case in which the mother’s work colleagues witnessed part of the attack while on a Zoom call and called the authorities,” District Attorney George Gascón said in a news release.
Brown was a faculty member at Pasadena City College for over 14 years, according to her social media. Most recently, she served as co-coordinator of its Black STEM Program initiative.
“So many memories about Carol and the amazing work that she did with so many of our students and the incredible spirit she had that was so positive, uplifting and helpful,” Dr. Cynthia Olivo, vice president of student services, told KCAL9.
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Dionne Shelter, a former student and current employee at PCC told the news station that Brown always made students feel at home during their time at the college.
“I honestly feel so heartbroken, I feel so sad,” she said. “When you don’t care where someone comes from, what they look like, what they might smell like or whatever, and you still treat them like they are the same as you, a doctor with a PhD or whatever, it’s amazing.”
Pasadena City College did not immediately respond to PEOPLE’s request for comment.
Deputies responded to the 3100 block of N. Marengo Avenue in Altadena, Calif., around 2:45 p.m. after Brown’s colleague reported witnessing “a possible kidnapping in progress,” the Los Angeles County Sheriff’s Department wrote in a press release.
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When they arrived, they found Preston in the driveway suffering multiple stab wounds. They discovered Brown’s body inside the home. Both were pronounced dead at the scene, the sheriff’s department said.
During the investigation, Cotton returned to the residence driving one of the victim’s cars and identified himself as a resident, according to deputies. He was detained on scene.
Authorities have not yet identified a motive for the attacks.
Cotton is being held on a bail of $4 million and appeared in court Monday, according to the LASD’s Inmate Information Center. It is unclear if he has entered a plea at this time, and a lawyer for Cotton could not immediately be identified by PEOPLE.