Los Angeles Unified School District Superintendent Michelle King on Friday announced she was retiring to focus on fighting a cancer illness that forced several prolonged absences last year.

King, 56, has been on leave since September, turning over administration of the nation’s second-largest school district to Acting Superintendent Vivian Ekchian. In a statement issued Friday in which she disclosed the cancer diagnosis, King said she intended to remain on leave through June before officially retiring after 33 years with the district.

“I am very thankful for the outpouring of support I have received from the entire L.A. Unified family, our community partners and my colleagues across the nation,” King said in her statement. “As I aggressively fight this illness, I ask that you continue to keep me in your thoughts and prayers.”

A separate statement from the LAUSD Board of Education confirmed that Ekchian will continue as acting superintendent until a permanent successor is chosen.

Prior to being named superintendent exactly two years ago, King, who graduated from a school in the district, served as a teacher and administrator. She was the first black woman to hold the post.

No additional details were released in the Board of Education statement on the search for a permanent successor.

Mayor Eric Garcetti described King as a close friend in a statement offering thanks for her dedication and leadership.

“Michelle King has devoted her entire professional life to Los Angeles’ young people — and her time as superintendent has brought phenomenal progress to students across our city,” the mayor’s statement reads. “LAUSD’s record graduation rates are a testament to her remarkable commitment, and it has been my privilege to work closely with her on making community college tuition-free for every district graduate, expanding after-school programs, making more campuses available for recreation, and creating new opportunities for students to get the work experience they need to build a more prosperous future for their families and communities.”

Economy, education, energy and transportation reporter Howard Fine can be reached at hfine@labusinessjournal.com. Follow him on Twitter @howardafine.