Travis Reinking -- who exhibited "mental instability" and was arrested last year for trying to enter the White House grounds -- was captured in the early afternoon after a more than 24-hour manhunt.
"A tip from the community is what led to the arrest," Nashville Mayor David Briley told a news conference.
The 29-year-old was to face four counts of criminal homicide charges for Sunday’s pre-dawn shooting that also wounded two people.
He was captured without incident at a wooded area near his home, refused to speak with authorities and asked for a lawyer, police said, adding that they found a semi-automatic weapon and ammunition in a backpack he was carrying.
After his arrest, police posted photos of Reinking in the back of a police car, looking disheveled and wearing a ripped maroon shirt and jeans.
"He looked like he was tired," said Nashville police lieutenant Carlos Lara.
Reinking is accused of using an AR-15 semi-automatic rifle to rain bullets at the Waffle House restaurant while wearing nothing but a jacket.
He was stopped by James Shaw, 29, a restaurant patron hailed as a hero for wrestling away the rifle.
Reinking then shed his jacket, returned to his nearby apartment home, put on clothes and fled, according to police.
The Nashville metropolitan area of 1.8 million people was on edge for more than a day as armed federal, state and local police looked for the suspect.
As the manhunt ended, the actions of Reinking’s father came into sharper scrutiny.
Reinking was arrested at the White House in July 2017, when he entered a restricted area of the presidential grounds.
He demanded to see Donald Trump and declared himself a "sovereign citizen," a designation used by anti-government extremists, according to The Tennessean newspaper.
Police rescinded Reinking’s firearms ownership authorization in the Midwestern state of Illinois, where he lived at the time.
They seized his four weapons and handed them to his father. But his father returned the weapons to his son, according to police.
"From our perspective, after the incident at the White House... we were able to effectively neutralize what we felt was the threat at the time by ensuring that he did not have the ability to purchase or own weapons," said FBI Special Agent Matt Espenshade.
Reinking’s father could face charges for his actions, said Marcus Watson of the Bureau of Alcohol, Tobacco, Firearms and Explosives.
"If you transfer weapons to a person that is knowingly prohibited, that could be a violation of federal law," Watson said.
Reinking’s mental health was also under scrutiny.
Nashville police spokesman Don Aaron confirmed that Reinking "exhibited mental instability over many months," but said investigators did not have a motive for the attack.
Reinking recently had been fired from a job at a construction crane company for exhibiting signs of paranoia, according to The Tennessean.
Family members had told police he believed singer Taylor Swift was stalking him, according to The New York Times.
Authorities confirmed that Taurean Sanderlin, 29, Joe Perez, 20, and DeEbony Groves, 21, were killed at the restaurant.
A fourth victim, 23-year-old Akilah Dasilva, died at a hospital.
Source from Vietnamnews.