One man was killed and a second man was in critical condition after a shooting Monday at the funeral of a known gang member.

Mary Sistrunk said her son, 21-year-old Sherman Miller, was killed in the shooting inside St. Columbanus Church.

Another man, 26-year-old, Deonte Ousley, was rushed to surgery in critical condition.

Police said both Miller and Ousley are "convicted felons and had a gang affiliation."

Sistrunk said she lost another son in a similar incident about four years ago and said she told Miller he needed to "let go of those people and get with God."

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The funeral, in the 300 block of East 71st Street, was for James Holman, who was shot and killed a week ago at 60th and Michigan. Gunfire reportedly broke out in the vestibule of the church as the funeral ended.

Eyewitness April Smith said she saw a man approach the church from 72nd and Prairie, then walk inside and start shooting. She heard at least 10 shots before seeing the man run out, drop the gun and take off, she said.

"This has to stop. If it's happening at funerals, it's going to continue to happen," she said.

Pastor Corey Brooks tweeted that gunfire broke out after he preached a funeral there.

"Please pray I believe people have been hit it is Chaos about 500 people here. This is Crazy!!" he tweeted.

"Two people shot and it appears that one is dead and one critical," he tweeted. "Please pray for Chicago. This is Horrible!!

Police could not confirm Brooks' description of the scene.

Brooks on Sunday said he is considering a bid for former Rep. Jesse Jackson Jr.'s vacated congressional seat in the 2nd District. Brooks became known as the "rooftop pastor" after holding a vigil atop a Super Motel to draw attention to Chicago violence. 

Four people were killed and 20 were injured in shootings over the long holiday weekend.

Police Supt. Garry McCarthy said Monday the police department's strategy to curb gang violence is working and the number of murders after May 1 has decreased year over year.

"I can't change what happened in the first quarter," McCarthy told reporters. "What I can do is fix it moving forward."