LOCATED: Chiu Wah Ng, 64, Of Libertyville Township

LIBERTYVILLE TOWNSHIP, Ill. (CBS) -- The Lake County Sheriff's office said an intellectually disabled man has been found after three days missing in Libertyville Township.

Chiu Wah Ng, 64, of the 16300 block of West Arlington Drive in unincorporated Libertyville, had not been seen by his family since 9 a.m. Friday, according to the sheriff's office. Ng was reported missing by his family on Sunday afternoon, the sheriff's office said.

Ng had left home on foot on Friday morning after a quarrel with a family member, the sheriff's office said.

Just after 7 p.m. Sunday, a Libertyville police officer on patrol saw a man walking on the sidewalk in the 400 block of Milwaukee Avenue in Libertyville, and recognized the man as Ng from a law-enforcement bulletin issued earlier in the day, police said.

The Libertyville officer spoke with Ng, confirmed that it was him, and worked with Lake County Sheriff's detectives to reunite Ng with his family, police said.