LOS ANGELES (AP) — The superintendent of the Los Angeles Unified School District says he will step down after his contract ends in June.

Austin Beutner made the announcement in a letter to the school board Wednesday. He is leaving as the nation's second-largest school district begins reopening classrooms shuttered for more than a year by the coronavirus pandemic.

Beutner said his three years at the head of the 600,000-student district was “the most rewarding job" he has held. He didn't say why he was leaving.

The school board issued a statement praising what it called Beutner’s “unwavering leadership during the extraordinary challenges” faced during the pandemic.