Suspected bank robber who shot police officer was arrested in 2010 for threatening Obama

The lone suspect in a weeklong bank robbery spree that included the killing of a police officer in Mississippi was arrested in 2010 after making online threats against President Barack Obama.

A Secret Service spokesman told the Associated Press that Mario Edward Garnett was living in Oklahoma City at the time of his arrest. He would not say how the case was resolved.

Garnett, 40, was fatally shot by a responding police detective just after robbing a bank in Phoenix, Arizona Saturday morning. He had previously been linked to a robbery at a bank in Tupelo, Miss., which resulted in the shooting death of police officer Gale Stauffer. Garnett allegedly ambushed Stauffer and his partner while they were making a traffic stop of a vehicle thought to be linked to the robbery.

Earlier Monday, surveillance photos taken from a Bank of America branch in Atlanta showed a man a man wearing a black-and-white patterned jacket trying to commit a robbery. He was wearing a black ski mask and black gloves and carrying a handgun.

After failing to get any money from a teller, the man demanded and received an undisclosed amount of money from someone who was using an ATM in the bank's lobby.

The FBI said Sunday that the identification of the man killed in the Phoenix robbery was "made based upon similarities" between the three robberies, "including the clothing worn by the bank robber, statements uttered by the bank robber during the robberies, and the robber's overall modus operandi, supported by other evidence and information collected during the course of this investigation."

"Additionally, cell phone records, obtained via court order, indicated that this individual's phone was in Atlanta, Tupelo, and Phoenix when the bank robberies were committed," the statement added.

A spokesman for the Phoenix Police Department said that Garnett was originally from the Midwest and had served in the U.S. Army for four years. He had no connections to the Phoenix area and had no prior criminal record apart from his arrest by the Secret Service.

The Associated Press contributed to this report.