Richard A. Brown, who served Queens for close to 28 years as its top law enforcement official, has died, his office announced on Saturday morning.

Brown, 86, had been battling from complications of Parkinson’s disease in recent years and announced in March that he was taking a leave of absence until June 1, when he planned to formally resign the office. He handed over his duties in an interim capacity to Chief District Attorney John Ryan, his top deputy, who announced Brown’s death.