A Georgia man pretended to be a friend who was a doctor for six months, treating up to 500 senior citizens across Columbia, according to Lexington County deputies.

Ernest Addo, of Austell, Ga., was arrested Friday and charged with unlawfully practicing medicine. Lexington County deputies are in Georgia, interviewing him and beginning the extradition process, Sheriff James Metts said.

Addo used documents from a friend who is a doctor in Orangeburg to convince Agape Senior Primary Care he was a physician. The company hired him in February, and he saw patients up until Wednesday, when he quit, deputies said. That was the same day that Addo's friend realized Addo had opened credit cards in his name and called police.

Investigators are trying to determine if Addo had any medical training and figure out what kind of treatment he was giving patients at the Agape facilities in West Columbia, Irmo and Columbia.

The sheriff said deputies are also investigating whether Addo should be charged with unlawfully prescribing medicine or with illegally getting wages from Agape. It wasn't clear if Addo had a lawyer.

Officials with Agape said all of Addo's credentials checked out and the name he gave them was given a good recommendation from his previous employer. The company is fully cooperating with investigators, said Chief Clinical Officer Janet DiNino in a statement.

Agape is shocked that someone would perpetuate such a fraud upon it and its patients," DiNino said. "Agape has taken immediate steps to protect its patients and ensure all care was appropriate."