The man arrested for the deadly shooting at a College Park megachurch has been down the road before.

Floyd Palmer, 52, pled guilty to shooting a man at a Baltimore mosque a decade ago. Palmer’s former mother-in-law said the shooting happened after an argument. In 2004 he was convicted of assault charges, but was deemed “not criminally responsible.” Palmer spent the next 18 months in a mental health facility. The victim is paralyzed.

It is not clear what led to the shooting Wednesday morning at Rev. Creflo Dollar’s World Changers Church International. But police say Palmer, 52, calmly walked into a prayer service and opened fire, with 20-25 people watching.

A witness says six shots were fired. Greg McDowell, 39, took one of the bullets and died at the church as Palmer calmly walked out, police said.

A massive manhunt ended around 4 p.m. when Palmer was arrested inside the Macy’s department store at Lenox mall in Buckhead.

“He was taken into custody without incident,” Fulton Co. police Cpl. Kay Lester told News/Talk WSB. “He was not combative. He did not have any weapons on his person.”

Palmer was a church employee until he resigned for personal reasons in August.

“He was mixed up and argumentative,” said Christine Singleterry of her former son-in-law. Singleterry told the AJC her daughter, who is deceased, divorced Palmer in the 1990s because he was abusive.

They had two daughters who are now grown.

Palmer’s alleged victim also is the father of two kids, but McDowell’s sons are much younger. He was a member of the church’s production crew and a facilities maintenance manager, police say.

McDowell was “tremendous leader, role model and father” said Ken Terry, one of the church’s pastors. “We have known him for years, since he was a little kid. He was the model dad.”

Members of the church who worshiped alongside McDowell were in shock.

“The devil comes in all disguises,” Kim Mathews told WSB’s Jon Lewis. “You say ‘wow this is my church home’ you wouldn’t believe it would happen to you.”

Creflo Dollar started World Changers Ministries in 1986 with eight members, according the church’s website. Its campus now occupies 81 acres, with services held in the 8,500-seat World Dome. Dollar is a regular on the Trinity Broadcasting Network.