A day after 17-year-old Brady Becker called for the firing of Detective Nicholas Breaux, claiming he was the victim of police brutality last week, the Jefferson Parish Sheriff’s Office on Friday released a detailed report that portrays the high school student as a drunken aggressor who threw the first punch at Breaux and tried to strangle the deputy while resisting arrest.

The five-page report, released a week after Becker was booked on four counts, including battery of a police officer and inciting a riot, roundly contradicts the version of events Becker put forth Thursday at a news conference at his mother’s house in Reserve.

While immediately disputed by Becker’s attorney, the report offers the fullest account to date of the Feb. 13 arrest, most of which was not captured during a 37-second cellphone video that shows Breaux, a mixed martial arts fighter, delivering four right hooks to Becker’s face.

Footage of the arrest, which has been viewed more than a quarter of a million times on YouTube, raised questions about Breaux’s use of force, even as Sheriff’s Office officials said they saw no evidence of wrongdoing on the detective’s part.

Becker, a student at St. Charles Catholic High School in LaPlace, filed a formal internal affairs complaint Friday, triggering what JPSO officials promised would be a “full-scale investigation” — a probe they had declined to open before the student appeared in person at the Sheriff’s Office.

David Belfield, an attorney who vowed to file a federal civil rights lawsuit next week on Becker’s behalf, dismissed the new incident report as “foolishness” and “a whole lot of BS.”

He had not reviewed the entire report late Friday evening but took issue with some of the assertions he had read, including the claim that Breaux and his partner approached Becker and his friends on two separate occasions and identified themselves as law enforcement officers.

Becker has maintained he had “no clue” Breaux was a deputy, saying he believed at first he was being assaulted by a “random person on the street.”

The report acknowledges that Breaux punched Becker in the face several times but said he did so “in hopes of gaining control of (Becker’s) violent behavior” after the two traded a series of blows.

Becker was so inebriated after being taken into custody, the report says, that deputies had to stop their vehicle so he could vomit as they left the parking garage of the Lakeside Shopping Center in Metairie.

Later, after Becker had been taken to Interim LSU Hospital, he allegedly asked Breaux and his plainclothes partner, Cory Porche, what had happened, saying he “did not have any recollection of what occurred on the parade route.”

Becker deflected a question Thursday about whether alcohol had played a role in his arrest, though his mother has not disputed he had been drinking. The incident report quotes Becker as admitting he’d consumed a half bottle of Crown Royal the night of the parade.

According to the report, Breaux and Porche had been patrolling the parking garage after the Krewe of Centurions rolled because the area “has been known for the use of illegal narcotics, fighting and underage alcohol consumption during the Carnival season.” Uniformed officers had been trying to usher “large numbers of people to their vehicles or from the area” after the parade, the report says, when several people in Becker’s group began shouting “F*** the cops.”

At 9:38 p.m., the report says, Breaux and Porche approached the rowdy crowd, described as numbering 20 to 30 people, identified themselves as law enforcement officers and told the youths “the parade was over.”

“The detectives then proceeded to walk away from the large group of people in the hopes the crowd would calm down and to see that the other civilians exited the parade route in a safe manner,” the report says.

Seconds later, the report says, the plainclothes detectives could hear the crowd again screaming “F*** the police,” a chant Becker allegedly initiated. “Becker was observed to be the main instigator,” the report says, “causing others to become more irate and aggressive toward the law enforcement” presence.

At 9:45 p.m., Breaux and Porche approached the crowd, which the report described as “growing out of control” and “refusing to vacate the parade route.” The detectives noted a “strong odor” of alcohol and “burnt marijuana emanating from the crowd.”

Breaux told Becker again that he was a Jefferson Parish Sheriff’s Office deputy, the report says, and Becker “pushed Detective Breaux in the chest, stating “F*** you, pig!”

Telling him he was under arrest, Breaux grabbed Becker’s left arm and tried to place him “in a prone position on the ground for handcuffing,” the report says.

Becker began punching the detective “in the face and chest area with his free hand,” the report says.

As Breaux and Becker struggled, the report alleges that “several other unknown subjects began punching Detective Breaux in the side of the head.” The report also says “an unknown white female” tried to grab Breaux’s gun at some point and that Porche pushed her away.

Asked why no one but Becker had been arrested, Col. John Fortunato, a Sheriff’s Office spokesman, said he had not seen the new incident report and declined to comment.

The report says Breaux feared Becker was trying to strangle him after the deputy took him to the ground. The 37-second clip shows Becker grasping at the deputy’s neck area — resistance described in the report as the student “grabbing Detective Breaux’s throat.” It says Becker submitted to arrest only after Breaux struck him several times in the face.

The report says Becker’s mother, Donnell, tracked her son’s cellphone to the hospital and arrived about 3:30 a.m. It says hospital security eventually asked her and her family to leave because they were “being loud and belligerent” with Breaux.

Becker was released from the hospital at 5:30 a.m. and booked into the Jefferson Parish Correctional Center. His booking photo showed two black eyes and other injuries he received from Breaux.