Story highlights The DNA matches a 2-year-old boy

Lagoon where body parts were found was drained

(CNN) The remains of a toddler found in a Chicago lagoon over the Labor Day weekend match the DNA of a missing 2-year-old boy from Rockford, Illinois, Chicago police said.

Kyrian Knox wasn't reported missing until two weeks after a dismembered body was found in Garfield Park near Chicago's New West Side. It's not clear when the boy was last seen.

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The body parts may have been in the lagoon "a week to two weeks" when they were found in early September, the police department's chief of detectives, John Escalante, told reporters at the time. "We don't think much longer."

Still, that may mean Knox had been missing about a month before authorities were informed.

His mother said the boy was staying with a family friend in Rockford while she was moving from Iowa to Chicago.

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