Mario Edward Garnett is the man responsible for robbing a bank and killing a Tupelo police officer.
Authorities have identified the man shot and killed by officers after attempting to rob a Phoenix bank.
FBI believes this is the same man who robbed banks in Atlanta and Tupelo and shot two Mississippi officers, killing one of them.
40-year-old Mario Edward Garnett has been identified as the suspect by Phoenix Police Officer James Holmes Sunday afternoon.
According to the Associated Press, Garnett was arrested in 2010 after making online threats against the president, a Secret Service spokesman said Sunday.
Secret Service spokesman Max Millien said, Garnett was living in Oklahoma City at the time of the arrest.
Authorities have connected Garnett to a Dec. 23 bank robbery attempt in Atlanta, a bank in Tupelo that same day, and the shooting death of one officer and the wounding of another just after the Tupelo robbery.
A Phoenix detective shot and killed Garnett just after he robbed a bank Saturday morning.
The FBI's special agent in charge, Daniel McMullen, in Jackson said records showed the suspect's cellphone was in Atlanta, Phoenix and Tupelo at the time of each incident.
McMullen also said at the press conference Sunday morning in Tupelo that there were similarities between the three bank robberies, including the clothing worn by the suspect, statements he made during the incidents and his overall modus operandi.