Four years after rising rapper XXXTentacion was ambushed, robbed and shot to death outside of a South Florida motorcycle dealership, one of four men charged in his killing has pleaded guilty.

Robert Allen, 26, of Lauderhill, pleaded guilty Friday to second-degree murder and robbery with a deadly weapon, the Broward State Attorney’s Office said in emailed statement.

“This was an open plea to the court, with no negotiated deal with the state,” the email said.

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Allen’s attorney, James Lewis, said he felt it was in his client’s best interest to enter the plea and cooperate with the prosecution against co-defendants Dedrick Williams, 26, of Pompano Beach; Michael Boatwright, 26, of Fort Lauderdale; and Trayvon Newsome, 24, of Fort Lauderdale.

Broward Circuit Judge Michael Usan, who is presiding over the case, has discretion in sentencing Allen with anything from probation to life in prison, Lewis said.

Williams, Boatwright and Newsome were indicted on charges of first-degree murder and robbery with a deadly weapon. They have each pleaded not guilty.

Lewis said the other three defendants’ trial will likely begin in January. Allen will be a witness for the state.

Dedrick Devonshay Williams, left to right, Michael Boatwright, Robert Allen and Trayvon Newsome were charged in the murder of South Florida rapper XXXTentacion. Allen pleaded guilty on Friday, Aug. 12, 2022. (South Florida Sun-Sentinel)

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XXXTentacion, born Jahseh Onfroy, was leaving the RIVA Motorsports dealership in Deerfield Beach shortly before 4 p.m. on June 18, 2018, when an SUV pulled up and blocked his BMW, an arrest warrant says. Two armed men jumped out of the SUV, robbed him and shot him multiple times.

The rapper was 20 years old when he was killed. After his death, his song “Sad!” rose to the top spot on Billboard Hot 100, the South Florida Sun Sentinel previously reported. The song’s music video recorded before the murder shows somber mourners filling church pews as he attends his own funeral.

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One of the gunmen took a Louis Vuitton bag from Onfroy’s car after he was shot, along with his cell phone, the key to his BMW and $50,000 in cash, the warrant says. The two men jumped back in the SUV and fled.

Surveillance video from the motorcycle dealership showed Onfroy arriving at 3:30 p.m. Two minutes later, the SUV parked outside the store, and two of the suspects walked inside, the warrant says.

One of the men, wearing bright orange sandals, bought a black neoprene mask. His orange sandals later helped investigators identify him as Williams. The second man was later identified as Allen, the warrant says.

A BMW sits idle after reports of a shooting in Deerfield Beach that killed rapper XXXTentacion on Monday, June 18, 2018. (John McCall / South Florida Sun Sentinel )

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They both then left the store and got back into the SUV before leaving the parking lot through one of the gates 10 minutes later. The men waited inside the SUV while parked outside of a nearby home until Onfroy pulled out of the dealership parking lot, when he was ambushed, the warrant says.

Williams was thought to be driving the SUV, and Broward Sheriff’s Office deputies arrested Williams at his home in Pompano Beach two days later, the first of the four to be taken into custody.

Williams told detectives he wanted to cooperate and tell them what happened that day outside RIVA Motorsports but was afraid “of being labeled a snitch when he went to prison,” the warrant says.

Boatwright’s fingerprints were found outside the driver’s-side door of the SUV, and Boatwright and Williams’ phones put them at the murder scene one minute before the shooting, the warrant says.

In the days following the murder, Boatwright’s phone history showed searches for Onfroy’s stage name and “accessory to murder,” the warrant says. He was identified as one of the two masked gunmen, the Sun Sentinel previously reported, and the second to be arrested.

Allen was the third to be arrested after detectives found him in Georgia. Newsome was identified as the other gunman and surrendered to authorities at his attorney’s office in Fort Lauderdale.

Attorneys for Williams, Boatwright and Newsome did not return messages seeking comment Friday afternoon.

Staff writer Rafael Olmeda contributed to this report.

Information from Sun Sentinel archives was used in this report.