Story highlights Funeral was for 19-year-old who was killed last week

Man arrived as mourners congregated in parking lot, police say

"Everybody hit the ground," one man says

Two people were killed and two were wounded Thursday near Atlanta while attending a funeral for a murder victim, police said.

The funeral was for Ryan Guider, 19, who was killed in DeKalb County last week, county police spokeswoman Mekka Parish said.

Parish said a man arrived as mourners gathered in the parking lot at Victory for the World Church in Stone Mountain, just east of Atlanta, and began shooting.

"Everybody hit the ground," one man told CNN affiliate WSB. "Everybody was just screaming and hollering and just running."

One woman told the station she hid in the bushes.

Parish said people at the funeral shot back and killed the man, but WSB reported that police were still looking for the shooter and had detained three other people.