A man who believes he could be D?Wan Sims, a 4-year-old boy who went missing in 1994 and is presumed dead, has submitted his DNA to police for testing.

Captain Ronald Taig of the Livonia Police Department tells PEOPLE authorities became aware of the 25-year-old after he contacted Michigan State Police on Dec. 5.

On Dec. 11 ? the 25th anniversary of D?Wan?s disappearance ? Livonia officers took the man?s DNA to be tested.

Before going to police, the man made posts on social media talking about his beliefs. He reportedly shared stories his parents had told him about his childhood before going to police with his theory.

?It?s very odd because he came here claiming that he wanted this to be confidential but then I find out that he?s on social media talking about this and, you know, kind of broadcasting it on those outlets,? Taig says.

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D?Wan was reported missing on Dec. 11, 1994, from the Wonderland Mall in Livonia. At the time, his mother, Dwanna Harris, told police she was shopping with him when he disappeared.

However, surveillance footage obtained by police during their investigators only showed Harris as the mall.

D?Wan?s mother became the focus of police suspicion, but the boy was never found. She has always denied any involvement in her son?s disappearance, Taig says.

Following the man?s claims, police reached out to Harris for DNA evidence. She told officers the man had contacted her her via Facebook but after failing to answer her personal questions, she blocked him. She and D?Wan?s father are both cooperating with investigators, Taig says.

Anyone with information on D?Wan?s case is urged to contact Livonia Police Department?s missing persons unit at 734-421-2900.