LAKEWOOD, Wash. -- A man with a long criminal history, who is known to Adre'Anna Jackson's family, is a potential suspect in the girl's death, KIRO 7 Eyewitness News reported.

The man is someone police are "looking at very carefully in the long and frustrating investigation" of the 10-year-old's death, KIRO 7 Eyewitness News reporter Kevin McCarty said.

The 49-year-old man was convicted of rape and is being held in the Pierce County Jail on charges of failing to register as a sex offender.

Lakewood police said the man is among several people they are investigating, but officials would not comment Thursday directly on the investigation.

The potential suspect is an associate of Adre'Anna's family and was someone she knew prior to her disappearance, KIRO 7 Eyewitness News reported. His whereabouts on the day Adre'Anna vanished are not known.

Spencer Grant, the 44-year-old transient who was questioned this week as a possible witness in the case, said he and others known to frequent the area where Adre'Anna's remains were found know the potential suspect.

The potential suspect is not facing any charges related to the Adre'Anna Jackson case.

Lakewood police said their investigation is still open and active, and are not ready to call the man a suspect.