This undated mugshot released by the Miami- Dade Corrections & Rehabilitation Department shows rapper XXXTentacion. Authorities say troubled rapper-singer XXXTentacion has been fatally shot in Florida. The Broward Sheriff's Office says the 20-year-old rising star was pronounced dead Monday, June 18, 2018 at a Fort Lauderdale-area hospital. He was shot earlier outside a Deerfield Beach motorcycle dealership. (Miami- Dade Corrections & Rehabilitation Department via AP)

DEERFIELD BEACH, Fla. — Troubled rapper-singer XXXTentacion was shot and killed Monday in Florida in what police called an apparent robbery attempt, authorities said.

The 20-year-old rising star, whose real name is Jahseh Dwayne Onfroy, was pronounced dead Monday evening at a Fort Lauderdale-area hospital, the Broward Sheriff’s Office said. He was shot earlier outside a Deerfield Beach motorcycle dealership.

XXXTentacion had been at RIVA Motorsports checking out inventory, the sheriff’s office said. He was in a black luxury vehicle and preparing to leave when two armed suspects approached him. At least one of them fired, and then both suspects fled the scene in a dark-colored SUV. Investigators don’t have a motive, and no arrests have been made.

Stephanie Martinez, a 29-year-old mother who lives in the neighborhood, was just coming back from the pool with her kids when she heard three shots. She drove to the end of the street and saw the rapper’s body in the car.

“He has his mouth open and his hand out. Two people went over and checked his pulse,” said Martinez, who also saw blood. “It’s just weird because he should’ve had security and stuff with him.”

On Twitter, his peers expressed shock and sadness.

Kanye West said: “rest in peace … I never told you how much you inspired me when you were here thank you for existing.” Producer Diplo posted a photo of the two together and said, “Thanks for inspiring me.” Travis Barker tweeted: “I’m at a loss for words… speechless #RIPXXXTentacion Loved collaborating with you. You were a true artist …”

And J. Cole said, in part: “RIP X. Enormous talent and limitless potential and a strong desire to be a better person. God bless his family, friends and fans.”

The entertainer, who sported dreadlocks and a number of facial tattoos, was a rising star and notched a No. 1 album in March with his sophomore effort “?” and had a top 10 hit with “Sad!” but was facing trial on charges that he beat up his pregnant girlfriend.

XXXTentacion racked up huge streaming numbers — on Spotify, his “Sad!” had more than 270 million streams and was on its Top 50 chart this week in the United States and globally. He also has several songs that have been declared platinum, including “Changes,” ”Roll in Peace” with fellow rapper Kodak Black and “Look at Me!”

In interview with XXL magazine, which named him an up-and-coming artist last year, the rapper cited Nirvana, the Notorious B.I.G. and Tupac Shakur among his musical influences.

“Obviously, I’m one of the greatest of this generation, the upcoming generation, as far as artistry. … And I say that humbly,” he said in a video interview with the outlet last year.

But much of his brief career had been mired in controversy. In 2016, he was arrested on charges including home invasion for a 2015 incident, and less than a month later was arrested on charges that he attacked his girlfriend, who was pregnant at the time, and was jailed, and later faced more charges including witness tampering.