Police are searching for a gunman who was caught on surveillance video opening fire and killed a South Carolina man visiting family in East Flatbush, Brooklyn on Saturday. NY1's Grant Greenberg filed the following report.

Graphic surveillance video captured the shooting of 24-year-old Trevonne Winn in East Flatbush, Brooklyn on Saturday. He was in town visiting family when when he walked on Nostrand Avenue near Glenwood Road, clad in white and talking on his cell phone.

The video shows a hooded man in dark clothing walk out of a nearby store, stand around for a few minutes and then fire two shots point blank.

Trevonne Winn

Distraught and defiant, Winn's mother, Tracy, rushed to Brooklyn from South Carolina when she got the news someone shot her son in an apparent case of mistaken identity.

"This is my child, this is my first-born child. I have to come all the way down here to find out that my child is dead and lying on the sidewalk here," said Tracy Winn. "The person that said you shot my son, you said you messed up and didn’t mean to shoot him. I’m here and I'm here to stay and I'm going to find out what happened."

Police say the shooter came right up to the victim, apparently thinking he was someone else, and fired the fatal shots.

A small memorial marked the spot where Winn was killed, as friends and family mourned the father of two children who had a third baby on the way.

Winn's twin sister and his mother want answers.

"He didn’t bother nobody. I don’t know what happened," said Winn's sister.

"I don’t know how they do it in New York, but in South Carolina, if something like this goes on, somebody is going to say something," said Winn's mother.

Anyone with information on the case should contact the Crime Stoppers hotline at 1-800-577-TIPS, or text CRIMES and then enter TIP577, or visit www.nypdcrimestoppers.com.