Authorities are searching for an elderly Hall County man who suffers from dementia.

Walter Robitaille, 82, left his Merlin Drive home in Oakwood at about 6 p.m. Wednesday, Hall County Sheriff’s Col. Jeff Strickland said. Robitaille was last seen driving a blue 2000 Buick LeSabre with Georgia tag DP9JK4.

Robitaille, who authorities say suffers from dementia and uses oxygen for a heart condition, was reported missing by family members Wednesday night after he failed to arrive at a Flat Creek Road business to pick up his wife, Strickland said.

Strickland said Robitaille was last seen about 8 p.m. by a parking attendant at Old Federal Campground. He asked directions from the attendant, drove off, and hasn’t been seen since, Strickland said.

A "Mattie’s Call" alert was issued to law enforcement agencies Wednesday night around midnight, and a state patrol helicopter was searching the southern end of Hall County area Thursday afternoon. In addition, the sheriff’s south end patrol units have been actively looking for Robitaille since last night, Strickland said.

Robitaille had a four-hour supply of oxygen for his heart condition when he left home, Strickland said.

Authorities believe Robitaille was in Marietta around 6:30 p.m. Thursday at an Exxon/Mobile gas station. Robitaille is 5 feet, 7 inches and 146 pounds, with gray hair and brown eyes.

Anyone with information about his whereabouts is asked to call 911 or 770-536-8812.