ATLANTA -- A man dies after a metro Atlanta concert – and now his family wants answers, and police want your help finding those responsible.

A family of a man can’t understand how a night of fun at a concert could end with him dead.

It happened at the Hi-Fi Buys Amphitheater during a concert by the group Korn on Sunday. Police say 30-year-old Andy Richardson was beaten by two other concert-goers.

Homicide investigators are looking into the beating. Andy Richardson passed away just after 2 p.m. Tuesday. He has been declared dead, but is on life support so they can harvest his organs for donation.

Gloria Richardson is trying to figure out how a night of fun could end with her son's death.

“Can you imagine your child goes to a concert and be killed for it, because of people out there fighting to have a quote unquote good time?” says Gloria Richardson.

Gloria is still trying to comprehend how her 30-year-old son, Andy, ended up brain-dead after he was attacked during a concert by the group, Korn, at the Hi-Fi Buys Amphitheater. She also can’t understand how the attackers got away.

“And I’m angry. I’m very angry. Why were the police not there to stop them,” says Gloria.

“We were all enjoying the concert, we were having a good time, until these two guys came around,” recalls Andy’s friend, Edgar Arellano.

Arellano says it all started after the two men were mosh-pitting.

“A mosh pit is just jumping around and pushing each other,” explains Arellano.

A sign at the amphitheater says that activity is not allowed. Arellano says Andy told the men to be careful not to hurt his pregnant girlfriend and a mentally-challenged child he had with them.

A fight broke out between Andy and the men, but it soon ended and the men left. Arellano says the men soon returned, and one hit Andy in the head with his fist, knocking him head first onto the concrete.

“He was unconscious. He had blood all over his face when I picked him up,” says Arellano.

Andy’s mother wants anyone who knows anything to give police a call. She’s also like the attackers to turn themselves in.

“I doubt that you will. But you really should and you should feel a lot of remorse because you cost a young man his life – for nothing,” says Gloria.

Police say they’re still investigating and only got a vague description of the suspects.