Updated

The tipster who helped crack the case of a beheaded 4-year-old girl went to police with his suspicions nearly a year ago and recently tricked the child's mother into providing a hair sample that he taped to a photograph and mailed to Kansas City, a community activist said Friday.

Police would not comment on what role the hair sample may have played in the arrests of Michelle M. Johnson (search), 30, and Harrell Johnson (search), 25, the girl's stepfather. The two agreed Friday to be returned to Kansas City to face murder charges.

Some of the hair came from the mother's brush, and she gave some of it to the tipster after he told her he would put it in a Bible under the 23rd Psalm to bring her good luck, said Alonzo Washington, a Kansas City community activist who has long championed efforts to identify the girl.

Washington said the tipster, who does not want his name released, first contacted police nearly a year ago and gave them all the pertinent details about the case, but investigators did not believe him.

"He is very clever, but he is not the most articulate-sounding person, and I think that made them dismiss him," Washington said. "They probably thought 'This is some Okie from Muskogee, and he doesn't know what he's talking about.'"

The child, who was almost 4 when she was found in 2001, was identified by police Thursday as Erica Michelle Marie Green (search). Her body was found near an intersection in Kansas City in 2001. Days later, her head was found nearby, wrapped in a trash bag. Police say the girl's head was cut off with a pair of hedge clippers.

Police knocked on doors in the neighborhood and even went to the house where the Johnsons were staying, police confirmed Thursday. Michelle Johnson answered the door and gave an officer a bogus tip on a suspicious man she said had been wandering the neighborhood.

In the months after the child became known as Precious Doe (search), hundreds attended candlelight vigils, volunteered to answer witness hot lines and passed out fliers with an artist's rendering of the girl. The FBI took blood samples from family members of missing black girls, and the case was featured on television's "America's Most Wanted."

Police investigators said the tipster was in touch with them numerous times since July 2004, but his information was incomplete. Then, on April 29, "He called back with a lot more detailed information," said Kansas City police spokesman Darrin Snap.

"We work the lead until the end," Kansas City Police Chief James Corwin said. "I mean that's what we do is we get a lead, we work it until the end and when it comes to a dead end. And you stop and some more information comes in and you work it again."

The tipster called Washington on Saturday and later sent him the hair sample and photo.

Washington got the photo and hair on Tuesday and provided it to police. Kansas City investigators then traveled to Muskogee to interview Michelle and Harrell Johnson, who were already in jail on unrelated charges.

According to court papers, Harrell Johnson beat the girl one night in April 2001 and the couple left her unconscious on the floor for two days. They did not seek medical help, the mother said, because both had warrants out for their arrest.

The child died, and the couple carried the body to a church parking lot, then through the woods, where the stepfather cut the girl's head off with hedge clippers, police said.

A $33,000 reward is being offered in the case, but Washington said the tipster was not influenced by the money.

"He said he just wanted to right a wrong," Washington said.