Police said the funeral was being held at Rock of Ages Baptist Church on Madison Street Friday morning when a family dispute broke out.
Police were called to the scene to deal with the dispute, and while they were attempting to defuse the argument when someone pulled out a gun and opened fire.
The person shot, who police have not identified or released their age or gender, suffered non-life threatening injuries, Maywood police said.
Two people were taken into custody at the scene.
An investigation into the incident is ongoing.
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