DETROIT (WXYZ) — The man suspected of the disappearance of 13-year-old Na’Ziyah Harris is already in custody in another case, according to Detroit police, but the man’s identity has not yet been released.

But relatives of the teenager believe he is the same man who had a romantic relationship with another of Na’Ziyah’s relatives and is a registered sex offender with a conviction for a sex crime against a minor.

PREVIOUS REPORT: Na’Ziyah Harris’ father speaks out to WXYZ

Na’Ziyah Harris’ father speaks out to WXYZ

The man in his 40s was convicted of third-degree sexual abuse in 2005 and spent about ten years in prison.

“He basically came home from prison and went back to his old activities,” said Jernell Smith-Holland, Na’Ziyah’s great-aunt, who said she was one of the relatives who tried to report inappropriate behavior by the same man in Macomb County a few years ago.

“This individual was named in all three CPS cases and nothing was done,” Smith-Holland said.

Na’Ziyah’s cousin Kewana Morton said she tried, too.

“It’s very frustrating. We insisted on informing not only the family but also the child welfare office long before Na’Ziyah disappeared.”

In March, while the search for Na’Ziyah was still ongoing, a teenager went to Detroit police and reported that the same man had sexually abused her in 2015, when she was just seven years old.

PREVIOUS STORY: Police search pond in Clinton Township in connection with missing Detroit teenager Na’Ziyah Harris

Police search pond in Clinton Township in connection with missing Detroit teenager Na’Ziyah Harris

This man is alleged to have sexually abused the girl in a house in Detroit from June 2015 to June 2016. He is accused of two counts of second-degree sexual abuse of a person under the age of 13.

PREVIOUS STORY: Relatives of missing teen believe a registered sex offender harmed her

Relatives of a missing teenager believe a registered sex offender harmed her

Morton and Smith-Holland are grateful that the girl came forward, and they hope charges will be brought against the person responsible for Na’Ziyah’s disappearance.

Last week, Detroit police filed a warrant request with the district attorney’s office in Na’Ziyah’s case. Prosecutors say they are currently reviewing the request and do not expect a decision this week.

“We just need closure,” Morton said. “We definitely need closure.”