Anthony Simmons, diagnosed with bipolar disorder and schizophrenia, was last seen leaving on foot from his group home at an unknown time, police say.
Officers responded to the missing person call at the 5000 block of Ga. Highway 85 in Riverdale.
Police describe Simmons as a black man, 6-foot-2 and about 208 pounds with black hair and brown eyes. His clothing description at the time of his disappearance is unknown.
Police ask anyone with information to contact the Clayton County Police Department at 770-477-3550 or call 911.
A Mattie's Call, Georgia's emergency missing alert for disabled or elderly persons, has since been issued.
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