JACKSON, Miss. — A man killed by police after robbing an Arizona bank is believed to be the same suspect who killed a police officer in Mississippi just five days earlier, authorities said Sunday.

According to federal court records, the man had also served a brief prison term for threatening to kill President Barack Obama in 2010 and had been ordered by a judge to receive mental health treatment.

The suspect was identified on Sunday by police as 40-year-old Mario Edward Garnett.

Garnett had pleaded guilty in federal court in his home state of Oklahoma in December 2010 to threatening to kill Obama. He was released from prison on July 19, according to the Bureau of Prisons website.

Wearing a mask, Garnett entered the bank in Phoenix on Saturday morning and displayed a handgun, filled a bag with cash from the vault and fled, the FBI said in a statement.

He got into a gun battle with a Phoenix police detective outside the bank and was shot and killed, the statement added, saying he was believed to be the same suspect who robbed a bank in the northeastern Mississippi town of Tupelo on Monday.

Tupelo police Officer Gale Stauffer, 38, was shot and killed at close range in the previous incident. Another officer was wounded.

Before the Tupelo shootout, the FBI said it believed Garnett had attempted to rob a bank in Atlanta, Georgia, which is about 300 miles east of Tupelo.

Authorities had launched a multi-state manhunt for Garnett and had offered a reward of more than $200,000.