The Harris County Sheriff's Office said the incident happened at the apartment complex at 10225 Wortham Blvd at about 7 p.m. on Saturday.
According to investigators, at least 30 people were at the pool. Deputies said the child's mother and aunt were at another part of the pool and were not watching him.
Investigators said that after the child went underwater, another person found him unresponsive, and he was pulled out.
A neighbor who was at the scene spoke to ABC13 and said he constantly relives the moment he realized the child needed help.
"We all jumped in to help," the neighbor said. "This boy was unresponsive. The mom and (another person) pulled the boy out of the water and we started to do CPR. We did all that we could to try to save his life."
Investigators said EMS administered CPR at the scene. Then, the boy was rushed to the hospital, where deputies say he was pronounced dead.
Detectives said they are working to learn how long the boy was underwater. The Sheriff's Office says it will be up to the District Attorney's Office to determine if charges will be filed.
SEE ALSO: Child in 'serious condition' after being rescued from Humble-area pool, sheriff's office says
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