A parent of a 13-year-old called National City police Monday evening because she suspected her child was "possibly having an inappropriate relationship with a former teacher," police said in a statement.
Police didn't release any details about the allegations, citing the victim's age and ongoing investigation.
The school district is only aware of one alleged victim, who is no longer a student in the school district, according to a statement National School District Superintendent Leighangela Brady sent NBC 7.
"We know that our entire school community is as stunned as we were by this news," Brady said in the statement. "The district will cooperate with law enforcement and cannot comment any further on the pending investigation. We will continue to do everything possible to keep our students’ safety, needs, and education first and foremost."
Ma posted bail Tuesday night and was released from Las Colinas Detention Facility, according to the San Diego County Sheriff’s Department.
She has been a teacher at the school since 2013, according to her LinkedIn page, and was named one of the "Teachers of the Year" by the San Diego County Office of Education for the 2022-2023 school year.
A blurb about her award reads: "She considers the relationships she maintains with her students her greatest accomplishments. She has spearheaded a schoolwide STEM improvement plan, bringing in outside organizations – including the Salk Institute, Scripps Institute of Oceanography, the Fleet Science Center and the San Diego Zoo – and providing opportunities for students to interact with professionals doing the work to better visualize a path to a rewarding STEM career."
For the award highlight, Lincoln Acres Elementary School Principal Kathy Melanese was quoted as saying, "I can’t imagine a more qualified and passionate educator to receive this honor.
"The creativity, initiative, collaboration, and 100 percent dedication Ms. Ma has for her students and the school is immeasurable. When students leave Ms. Ma’s room, they are more confident students, more engaged citizens and more thoughtful adolescents who know they are loved."
The school district and Ma could not immediately be reached for comment.