Kansas City, Mo. ? Police have received more than a thousands tips since the decapitated body of a little girl who came to be known as Precious Doe was found just over four years ago, so far with no luck in determining who she was.

Now, for the second time, they’re checking out information from one of their tipsters, an Oklahoma man who called back last week. On Tuesday, police from Kansas City and Muskogee, Okla., questioned two Muskogee residents about the slaying.

Records showed the pair were in custody on unrelated charges, the Tulsa World reported Wednesday. KMBC-TV in Kansas City reported Tuesday night that more Kansas City investigators would head to Oklahoma on Wednesday.

The tipster who called police last week had said he was related to the slain child, whose head was found near her body, but the initial investigation of his tip didn’t produce any solid leads.

When he called again last Friday, he said he knew the identity of the girl, knew her mother and knew who killed the child, who was believed to have been about 3 years old. He said the mother and the killer were from Muskogee, Okla., and had driven to Kansas City in the spring of 2001 to look for work.

He told The Kansas City Star he is confident the child was Precious Doe, saying her body was dumped after she was killed at a Kansas City home.

Two police detectives were going to Oklahoma on Wednesday to seek more information, one of the few times investigators have traveled beyond the Kansas City metropolitan area to check out tips. In 2001, FBI agents checked a tip that the slain girl resembled a girl from Jamaica, and the following year Florida investigators helped rule out that a child missing in that state was Precious Doe.

During the weekend the Oklahoma man called Alonzo Washington, a community activist who has championed efforts to find out who Precious Doe was. On Tuesday he received a package containing a photo of the woman the man maintains is the child’s mother. She is pictured with several children, including one that the Oklahoma man believes to be Precious Doe.

After Washington showed him a copy of the photo, homicide Sgt. Dave Bernard said one of the children does resemble the girl, but added, “I’m not going to make a judgment just on a picture. We’ve seen likenesses before.”

Police said the only way they could learn more was to go to Oklahoma.

“I’ve got nothing to say this tip is more promising than any of the other leads,” Bernard said. “We’ve had these kinds of leads before and they haven’t panned out. We try not to get too excited. We just need to go interview more people and see what we find out.”

The police probably will seek a DNA sample from the woman mentioned by the tipster. At least 17 DNA tests have already been conducted in the course of the investigation.

Bernard said police are also pursuing a promising scientific test that could pinpoint the region of the country where the little girl lived. He said that last year the FBI got him in touch with a Salt Lake City laboratory that could study teeth, bones and hair for various stable isotopes deposited from drinking water.

Police are still collecting samples from Precious Doe’s remains to send to the lab, and the testing could take three to six months.