The man accused in the fatal shooting of a 16-year-old boy Monday in an apartment off Airline Highway was in the country illegally and had been arrested in Baton Rouge five years earlier on gun and drug charges — a case that local prosecutors said they were told would result in his deportation.

But it was unclear Tuesday whether 49-year-old Octavio Bringas, of 4747 Southpark Drive, Baton Rouge, was ever deported and why he was in Baton Rouge.

Bringas was again arrested Monday as he was fleeing down Interstate 10 after he fatally shot and killed Darius Plummer while the two were alone in Bringas’ apartment at about 1 p.m., according to an East Baton Rouge Parish Sheriff’s Office report.

Bringas was arrested by State Police in Lake Charles around 3:30 p.m. Monday, and brought to Baton Rouge later that night where he was booked into Parish Prison on a count of second-degree murder.

His Monday arrest warrant notes that he is an “undocumented person living in the United States.”

Derrick Ambrose, 39, Plummer’s cousin, said the teenager was friends with one of Bringas’ sons and the boys had gone to the apartment to celebrate Plummer’s 16th birthday.

Investigators say Plummer and Octavio Bringas were the only two in the apartment at the time of the shooting. The teenage friend had stepped outside, Ambrose said. 

Bringas told a family member on the phone that he was playing with a gun when it discharged, striking Plummer. He added that he was not coming back and that he would not talk with police, according to the report.

Trina Plummer, 43, Darius Plummer's mother, said her son became best friends with Bringas' son when her family lived in the same apartment complex as the Bringases.

She said she had no idea that Bringas was living in the U.S. illegally or of his past arrests. Trina Plummer said she only knew that their sons were best friends and she had no reason to think Octavio Bringas was a bad person.

She said Darius even went to stay with the Bringas family at one point when her own family was going through a hard time. She added that Bringas' son is also a good kid.

However, Trina Plummer said, she still has questions about what happened Monday.

“In the back of my mind I just don’t understand, why would you be playing with a gun around my baby’s head?” Plummer said. 

Her family had plans to see the movie "Get Out" at 4:40 p.m., but Darius asked his mom if he could go spend time with his best friend first.

“My son said, ‘Mom, can I go? … Because (his best friend's) daddy says he has something for me for my birthday,’” Trina Plummer said. “Now in a joking way I’m like, 'What did he have? A bullet?'”

Her son's friend later told Trina Plummer that it was a pair of shoes because Darius Plummer loved shoes and clothes.

Bringas was previously arrested in March 2012 after a Baton Rouge police officer pulled him over for driving erratically.

In the 2012 arrest report, authorities noted Bringas did not have a "legal presence in the U.S." and booked him on a count of operating without lawful presence in the U.S.

Authorities said they found cocaine and a handgun in the pickup truck Bringas was driving at the time.

The East Baton Rouge Parish District Attorney's Office charged him with possession of cocaine at the time.

But District Attorney Hillar Moore III said Tuesday Bringas failed to show up to the 2012 court dates in the case.

When his office moved to forfeit his bail in July 2012, Moore said, an attorney for the bonding company reported that Bringas had been deported by federal authorities.

The case against Bringas was dismissed, according to court documents. Moore provided a copy of the bill of information charging him with cocaine possession. In a handwritten note scrawled across Bringas' name and personal information, a prosecutor wrote that he "has been deported, 7/19/12."

But it is unclear whether he was ever deported. A spokesman for U.S. Immigration and Customs Enforcement said Tuesday he was looking into the matter.

Bringas was also arrested in March of 2015 in Baton Rouge on second-offense DWI, reckless operation, driver’s license not in possession and two counts of hit and run. It is unclear how or if that case was resolved.

Immigration lawyer Kathleen Gasparian, who was not familiar with the case and could not comment on specifics, said there are a lot of reasons why Bringas may not have been deported and that it doesn’t necessarily mean there was a breakdown in the process or someone didn’t do their job.

“Most of the time (the criminal justice system) works really seamlessly,” Gasparian said. “Occasionally there are times where that doesn’t really happen. That could be because there was a bigger fish that day like ICE (U.S. Immigration and Customs Enforcement) had other priorities or ICE wasn’t notified or it wasn’t appropriate for ICE to be notified that day.”

Sheriff's Office investigators say Bringas is now accused of fatally shooting Plummer. When deputies arrived, they found Plummer lying on the kitchen floor with one gunshot wound, but could not find anyone else at the apartment, according to Bringas’s arrest warrant.

Ambrose, Plummer's cousin, said he did not know Bringas or the son, but said he was angry after finding out that Bringas was living in the country illegally.

“That’s what Donald Trump is trying to get rid of,” Ambrose said. “In a situation like that, what can you do but send him back to his country? … I don’t know how they’re going to go about that. I know a lot of people dislike Donald Trump, but at the end of the day, he’s trying to protect.”

Ambrose said he has a lot of questions about the incident that led to the death of his cousin, who he remembers as a teenager who goofed around with relatives while they played basketball as a family.

“We want to know what happened,” Ambrose said. “Was there a motive or was it an accident? If it was an accident, why was he playing with a loaded gun in front of a kid?”

Follow Emma Discher on Twitter, @EmmaDischer.