Los Angeles police responded to the single-vehicle crash around 2:30 a.m. in the 11200 block of Ventura Boulevard.
Rip to the homie Rasual Butler & his wife!! Condolences to the butler family & friends. Damn Bro 🙏🏽😪— Matt Barnes (@Matt_Barnes22) January 31, 2018
Investigators said Butler's Range Rover was traveling between 60 and 90 mph around a curve on Ventura, where the posted speed limit is 30 mph.
The vehicle veered out of control, sheared three parking meters, careened through a concrete wall and overturned several times before landing in a nearby parking lot. First responders had to use the jaws of life to extract the victims from the smashed SUV.
Butler, a La Salle University alum, was chosen by the Miami Heat in the second-round of the 2002 NBA draft. He played three seasons in Miami and went on to stints with the Clippers, Hornets, Bulls, Raptors, Pacers, Wizards and Spurs.
On Wednesday, several of Butler's former teams and teammates issued statements of condolences for him and LaBelle, a onetime "American Idol" contestant.
"The L.A. Clippers are deeply saddened by the loss of Rasual Butler and his wife, Leah LaBelle," the team said in a statement. "Rasual will long be remembered not only for his accomplishments on the court but for his vibrant personality, positive outlook and the compassion he had for everyone around him."
Police believe excessive speed was a factor in the crash.
"This is a horrific scene and a tragedy that could have been prevented. This is clearly, at this point, an issue related to speed. It's something we all have control over," said LAPD Capt. Andrew Neiman.
Investigators were looking into whether drugs or alcohol were a factor in the wreck.
Earlier, Butler and LaBelle had been bowling at a Pins in Studio City, the manager of the bowling alley confirmed. They left around 1 a.m. when the venue closed.
A friend who was with the pair at the bowling alley said he is in disbelief. "Rasual and Leah are very, very, very loved," he said. "Respected in the community, honorable, clean family. Amazing talent between the both of them. Rasual is just, I mean he's just like a big brother. One of the best guys."
Other friends and loved ones of the couple were seen Wednesday at the scene of the crash praying and embracing.
ESPN contributed to this report.
Rest easy my brother. See you when I get there!!! pic.twitter.com/Npsnib7k5t— Allen Iverson (@alleniverson) January 31, 2018