The killing is being investigated as a possible road rage incident, said sheriff's spokesman Col. John Fortunato. Fortunato. Officials identified the suspected gunman as Ronald Gasser, 54, who remained on the scene and was being questioned by homicide detectives.
Authorities say Gasser was released from custody overnight. Fortunato told media outlets that Gasser has not been charged and the shooting is still under investigation.
According to a report by NOLA.com, a witness in Terrytown saw two men in an argument near an intersection. One man was yelling at a second man, McKnight, who was trying to apologize. The witness said the man who had been yelling shot the second man multiple times, then paused and yelled a final epithet before firing on the man again.
Fortunato said the incident took place at 2:43 p.m.
McKnight, 28, committed to USC under then-coach
He was drafted in the fourth round of the 2010
McKnight is the second NFL player this year to die as a result of a possible road rage incident.
McKnight's relationship with USC was somewhat strained after he was not allowed to play in the final game of his junior season, in 2009, while USC investigated him for allegedly receiving improper benefits. He would leave USC soon afterward.
USC's current and former players and coaches have reacted with notes of shock and sadness on social media.
USC Coach Clay Helton posted, "Saddens me to hear the news about Joe McKnight. Our prayers go out to the McKnight family."
Bush said on Twitter, "this one hurts bad."
8:25 a.m., Dec. 2: This article was updated with the suspected shooter's release without being charged.