Ultimately, it may have been a simple traffic dispute Thursday that left a St. Charles Parish Sheriff’s Office deputy — a husband and father of four — with one bullet lodged behind his eye, another in his chest and a third in his arm.

Authorities say 58-year-old John Paul Devillier, in town for the funeral of a family member, grew agitated with veteran Deputy Burt Hazeltine after having to wait at an intersection near an elementary school in Paradis, where Hazeltine was directing traffic.

The Sheriff’s Office said Devillier returned to the intersection a few minutes later, lured the deputy toward his truck and then opened fire through the windshield, striking Hazeltine three times.

Sheriff Greg Champagne, speaking outside Interim LSU Hospital in New Orleans, where Hazeltine was scheduled to have surgery Thursday night, said Devillier was captured by deputies after a short “tussle.”

Devillier, who investigators believe suffers from “mental issues,” lives at the Value Place Motel in Gulfport, Mississippi, and was in town for a funeral, authorities said. He was in possession of two guns.

During a news conference, Champagne said investigators were studying Devillier’s past for signs of what might have set him off Thursday. So far, they know that he was divorced and was arrested on domestic violence and aggravated assault counts in 2013. That year, he also was fired from his job with the Transportation Security Administration for poor conduct, Champagne said.

Late Thursday, Hazeltine, who has worked for the Sheriff’s Office for 12 years and is assigned to the Traffic Division, was in stable but guarded condition, Champagne said.

He said Hazeltine was alert Thursday morning and kissed his wife, who was by his side at the hospital.

“It was very emotional for us,” Champagne said. “As far as us being involved in violence like this with a shooting, I don’t remember the last incident, and I’ve been doing this for 19 years as sheriff. So unfortunately, it can happen anywhere at any time — even in Paradis, Louisiana, where you would least expect it.”

The shooting occurred about 8:50 a.m. near the intersection of U.S. 90 and Louisiana Street, where Hazeltine was directing traffic near J.B. Martin Middle School.

Devillier had passed through the intersection and started arguing with the deputy because he hadn’t stopped traffic to let Devillier pass, according to a statement from the Sheriff’s Office.

Devillier then stopped at his father’s house a few blocks away and phoned Champagne’s office, telling the chief deputy there that he was an agent for the Naval Criminal Investigative Service, or NCIS, and demanding that the sheriff meet him at a nearby store, according to the statement.

After he returned to the intersection, Devillier allegedly beckoned the deputy over to his truck. As Hazeltine came closer, he spotted a handgun on the dashboard, drew his own gun and asked to see Devillier’s hands. At that point, Devillier held the gun upside down out of the window and fired several times through the windshield with another weapon, according to the Sheriff’s Office.

Although hit several times, Hazeltine was able to return fire and radio for help, the Sheriff’s Office said. He was hit in the face, the torso and the upper arm.

When more deputies arrived, Devillier tossed both guns from the truck and was arrested.

Deputies were able to make it to the scene quickly because members of the sheriff’s special response team were holding a training exercise nearby. Their practice scenario: responding when an officer is wounded.

“Sure enough, they had the opportunity, unfortunately, to put it into practice,” Champagne said.

Hazeltine wasn’t wearing a bulletproof vest at the time of the shooting.

“For whatever reason, he decided not to wear his bulletproof vest this morning, probably thinking, ‘What could happen just working a traffic detail?’ ” the sheriff said.

Both J.B. Martin Middle School and R.J. Vial Elementary School were placed on lockdown until the area was considered safe, said Stevie Crovetto, a spokeswoman for the parish school system.

A man who answered the door at Devillier’s father’s home declined comment. Neighbors said an older couple had moved into the home in the last couple of years but that they hadn’t met the younger Devillier.

Robert Doublet, 71, of Bayou Gauche, said he was standing in a nearby store when the shooting happened; he said he heard at least a dozen shots.

“All I heard was gunshots,” he said.

The wounded deputy attends Thibodaux First Assembly of God twice a week, said Liz Kreamer, who serves as children’s director at the church.

“He’s here when the doors open,” she said. “I could not ask for a better volunteer and a better support person for our kids over here.”

Kreamer recalled Hazeltine driving back from a shift in St. Charles Parish to help clean up after an Easter “extravaganza” for the children.

“He’s a dedicated dad,” she said, and a “very, very devoted husband.”

He and his wife, Mandy Hazeltine, “are very devoted to their faith and also people in need — hurt people. They’re always there to reach out to people in need, and they’re also willing to give their time,” Kreamer said.

Devillier’s alleged outburst is the latest in a series of high-profile violent incidents in the New Orleans area involving men who reportedly had mental health issues. After Richard White was shot March 20 while attacking a TSA agent at New Orleans’ Louis Armstrong International Airport with a machete, Jefferson Parish Sheriff Newell Normand said the taxi driver had a history of mental illness.

Earlier in March, 47-year-old Alvin Richardson allegedly shot and killed his friend in a truck and tossed his body onto South Broad Street. Richardson was diagnosed with schizophrenia in 1991 after shooting a New Orleans police officer. He was caught in March after calling Gretna police from a pay phone and telling them that people were “coming in to get me” at his hotel.