Sims, a 20-year-old junior from Baton Rouge, was shot during an altercation outside a Subway restaurant across from Southern's football stadium around 1:25 a.m. ET Friday. A video obtained by WBRZ shows several men fighting in the street outside the restaurant. A gunshot can be heard, and Sims can be seen falling to the ground before the remaining men started running from the scene.
Sims was transported to a local hospital, where he died from a gunshot wound, according to Baton Rouge police.
"We are all devastated," LSU coach Will Wade said in a statement. "We need your prayers for Wayde, for his family, for all of us. We are heartbroken."
Wade said he was told about the shooting early Friday morning and then went to the hospital. He told the team at 6:30 a.m., when they had originally scheduled a morning workout.
"We want to remember Wayde, what a great person he was," Wade said at a news conference. "Besides the fact he had the best impression of me on the team, he was just an unbelievable person and was continuing to grow and had just done a great job building a bridge with our team. That's what makes it so tough for all of us, and for our team as well, is everybody liked him. Anybody he came in contact with, automatically just loved him, loved his personality. He was just a blast to be around at all times."
Wade said he didn't have further details on what happened.
Sims, a 6-foot-6 forward, averaged 5.6 points with 2.9 rebounds in 32 games last season. He was the Louisiana 2014-15 Gatorade Player of the Year after leading University Lab High in Baton Rouge to three consecutive state titles from 2014 to 2016.
His father, Wayne Sims, also played basketball at LSU from 1987 to 1991.
"This world we live in of athletics, it has its ups and its downs. And there's no lower downs than what happened last night," athletic director Joe Alleva said. "It was -- it is -- an absolute tragedy when a young life gets cut off so senselessly. ... This may be the saddest day I've ever experienced in my career."
LSU teammate Aaron Epps shared his thoughts about Sims on Twitter early Friday morning.
"We are stunned and shaken," LSU President F. King Alexander said. "To say we are grief-stricken is an understatement. Wayde was a beloved member of the LSU community whose leadership was treasured by his coach and his teammates. I knew him personally and liked him tremendously. The void left by his passing will be immense, and we ask that you keep his family in your prayers."
LSU will hold a moment of silence prior to the No. 5 Tigers' football game against Ole Miss on Saturday (9 p.m. ET, ESPN). Football coach Ed Orgeron said he planned to discuss Sims' death with the team on Friday.
"This was his city," said linebacker Devin White, a friend of Sims'.
Sims had ties throughout the LSU basketball community. He was recruited by former LSU coach Johnny Jones, who is also his first cousin. Jones and Sims' father Wayne grew up together in Baton Rouge, La., Jones told ESPN. Stanley Roberts, the former first-round pick who teamed with Shaquille O'Neal at LSU to form the most powerful frontcourt of the early '90s, is Sims' godfather.
Jones, now head coach at Texas Southern, said he left Houston on Friday morning to see the family in Baton Rouge.
"I watched him grow up from a little kid to the man he is now," Jones said. "People enjoyed being around him. He had the ability to be the life of the party."
Information from ESPN's Myron Medcalf was used in this report.