What led up to Garrett Foster's death at an Austin protest Saturday night

A peaceful Black Lives Matter rally turned violent Saturday night when a person drove up to a crowd of protesters on Congress Avenue before stopping, shooting a man and quickly driving off, according to newsreports, Facebook Live video and police.

The victim, identified by his family and later by police as 28-year-old Garrett Foster, died at Dell Seton Medical Center. No other injuries from the incident were reported, but police said that a second person in the crowd drew a weapon and fired at the car as it drove away. Both shooters were questioned by police, but both have since been released.

Much of the hours-long march was live-streamed on social media, including around the time the suspect shot Foster. Gunshots can be heard during this Facebook Live video.

The incident began around 9:50 p.m. when the suspect, driving down Fourth Street, honked at protesters before turning and speeding down Congress Avenue. The car came to an abrupt stop after appearing to hit an orange barrier. Several protesters then approached the car, including Foster, who may have been holding a rifle, police said. The driver of the car then pointed a gun out his window, fired several times and left the scene.

Foster had been attending the protest with his fiancé, a quadruple-amputee, and was pushing her wheelchair, according to Good Morning America, which spoke to Foster's mother.

A protester who had seen Foster before said he often brought his rifle with him, the Austin American-Statesman reported. His sister told the newspaper that she did not believe he would ever point a gun at someone.

Foster and his fiancé, Whitney Mitchell, had attended many protests peacefully over the past few months, according to his mother and other protesters. After initially dispersing following the shooting, Mitchell and several dozen other protesters reconvened by the Austin Police headquarters early Sunday morning. Mitchell was surrounded by protesters chanting Foster's name and sharing their condolences.

A GoFundMe page has been set up as a memorial to Foster.

This story has been updated with new information.