The search for Relisha Rudd in a Northeast Washington park began to wind down Wednesday with no sign of the missing 8-year-old girl, despite a week spent trudging through underbrush, diving into a river and ponds, and crisscrossing 700 acres of land.

D.C. police said that on Thursday, they will continue to comb through parts of Kenilworth Park and Aquatic Gardens, but they added that the operation there is being scaled back and could end this week.

“With the information we had, this was our best chance” to find Relisha, Assistant Chief Peter Newsham told reporters. Authorities vowed to keep up the quest for the girl but said tips have slowed. Police, firefighters, cadets and volunteers have looked in manholes and culverts, gone into vacant houses and emptied trash bins.

Police said they concentrated their search on the park along the Anacostia River based on a tip and because Relisha’s suspected abductor was spotted there after he bought 42-gallon trash bags around the time Relisha was last seen on March 1.

“We came here based on a theory, and theory was based on information we could confirm that potentially we would find Relisha in this area,” Newsham said.

Newsham urged people to keep calling in tips, and Timothy A. Gallagher, special agent in charge of the criminal division of the FBI’s Washington field office, promised that authorities would continue looking for the girl. “We had children we recovered several years later,” he said. “We do not stop.”

Police said they went to the expansive grounds of the park looking for a “potential grave site” for Relisha, who vanished in February. Relisha was believed to be with a janitor at the District homeless shelter where she lived with her mother and three younger brothers. The girl’s mother had allowed Relisha to go with the janitor.

[Read timeline of events]

Instead of finding Relisha, police stumbled on the janitor’s body. Kahlil Malik Tatum, 51, was found dead Monday of an apparently self-inflicted gunshot wound to the head. Police said it appeared that his body had been in a shed in the park for 36 hours to a few days.

That leaves open the possibility that he shot himself after police began searching the park March 27. Newsham cautioned, however, that cold weather could have preserved the body for a longer period.

Police first started searching for Relisha on March 19, after a counselor at her school inquired about her mounting absences and tried to find Tatum, who had been listed in school records as her doctor.

The next day, police found Tatum’s wife dead of a gunshot wound in a room at an Oxon Hill motel. Tatum was charged in her killing.

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