The Memphis Grizzlies suspended star point guard Ja Morant after he was seen brandishing a gun at a nightclub in an Instagram Live video.
The 23-year-old posted a clip appearing to show him holding the firearm to the side of his head in a club after the Grizzlies away loss to the Denver Nuggets on Friday night.
The NBA announced it was investigating the incident after the clip went viral on social media.
“We are aware of a social media post involving Ja Morant and are investigating,” NBA spokesman Mike Bass told ESPN.
The Grizzlies tweeted that Mr Morant would be away from team “for at least the next two games”.
Mr Morant was already facing scrutiny after he was accused of punching a teenager and threatening a security guard in separate incidents in Memphis last summer.
In a statement released through his agent Jim Tanner on Saturday afternoon, Mr Morant said: “I take full responsibility for my actions last night. I’m sorry to my family, teammates, coaches, fans, partners, the city of Memphis and the entire Grizzlies organization for letting you down. I’m going to take some time away to get help and work on learning better methods of dealing with stress and my overall wellbeing.”
Mr Morant will miss the Grizzlies’ trip to Los Angeles for games against the Lakers and Clippers.
Earlier this week, the Washington Post revealed that Morant was the subject of two police complaints after incidents in Memphis last July.
The point guard was allegedly involved in an altercation with the head of security at the Wolfchase Galleria mall after his mother got into a dispute with an employee at Finish Line shoe store.
Then four days later on 26 July, Mr Morant was also accused of repeatedly punching a 17-year-old in the face at his Memphis mansion.
The teenager, who told police he had considered Mr Morant a mentor, had been invited to a play during a game of pickup basketball.
After the teen had reportedly thrown the basketball at Mr Morant, catching him on the chin, the basketball superstar punched him nearly a dozen times, leaving with a “large knot” on the side of his head after the violent encounter, according to the police report.
Mr Morant then went into his house and returned appearing to have a firearm tucked in his pants, the teenager told authorities. He later told police during an interview that he had acted in self-defense.
Mr Tanner described the incidents as “unsubstantiated rumours and gossip” put out by people “trying to tear Ja down”.
