UPDATED: April 2, 2014 9:33 a.m.

WASHINGTON (WNEW/AP) — The body of a man found dead in a park of an apparent suicide has been positively identified as that of a murder suspect who was the last person seen with a missing 8-year-old D.C. girl, police said Tuesday.

The body of Kahlil Tatum, 51, was found in a heavily wooded area of Kenilworth Park in northeast Washington where police have been searching for Relisha Rudd. Police found his body Monday and confirmed Tuesday that he died of an apparent self-inflicted gunshot wound.

Tatum was a janitor at the city homeless shelter where Rudd had been living with her family.

The search continues for 8-year-old Rudd on Wednesday. If police do not find any clues by the end of the day, the search will be considered complete at the Kenilworth Park.

Multiple law enforcement agencies, including the Metropolitan Police Department and FBI, are continuing to search for Rudd elsewhere as they follow up on leads. Rudd’s disappearance triggered a massive Amber Alert that eventually blanketed the eastern seaboard.

The discovery of Tatum’s body was a shock for police because they were focused on finding Rudd, Washington Police Chief Cathy Lanier said Monday. Lanier said at an afternoon press conference Tuesday that it appears Tatum’s body had been in the park for at least 36 hours but possibly several days.

“This discovery was a shock for us,” Lanier said. “We were very focused on finding Relisha and that’s what we came here for. … We’re not finished. That search is continuing.”

Around 100 people marched along Martin Luther King Jr. Avenue in Southeast a few hours after police announced the discovery of the body. WNEW’s Cameron Thompson says Rudd’s great-grandmother was also present during a candlelight vigil for the missing 8-year-old girl.

Police began searching for Rudd in the 700-acre Kenilworth Aquatic Gardens last week in an operation aimed at recovering a body, although Lanier said she had not given up hope that Rudd was alive. Hundreds of people, including divers, have participated in the search that Lanier said could be finished by the close of the day Wednesday or at some point Thursday.

Following a weekend of inclement weather, authorities returned to the park Monday to continue searching for the girl who was last seen alive on March 1.

The search began March 20, after authorities discovered Tatum spent more than two hours in that area shortly after purchasing a number of 42-gallon contractor style garbage bags, a shovel and lime on March 2.

Authorities were able to track Tatum’s movements by reviewing his cell phone usage, a police source told WNEW’s John Domen.

“We cannot ignore the possibility that he may have killed her,” Lanier has stated. She says authorities working the case will leave no stone unturned.

There are also a large number investigators following up on leads outside the park, as well, Lanier says.

Lanier also revealed at a press conference last week that police now know Tatum had contact with up to four girls at the homeless shelter where he worked and where Rudd’s family had been staying.

Investigators are following up with them.

Lanier said on March 21 that police plan to reach out to the community for assistance searching for the girl this week.

Prince George’s County Police had charged Tatum with the murder of his wife a hotel room two weeks ago.

Lanier said there is no evidence Rudd was with Tatum at the time the murder occurred.

Tatum was added to the FBI’s “Most Wanted” list last week as the search for the missing girl was extended to Atlanta, where Tatum was believed to have ties. Digital billboards displaying photographs of Rudd and Tatum were posted along roadways from Pennsylvania to Florida.

Tatum posed as a doctor and told school administrators that Rudd had been sick to explain repeated absences from class last month, according to Beatriz Otero, D.C. Deputy Mayor of Health and Human Services.

Shamika Young, Relisha’s mother, provided officials at Payne Elementary School in the District with the name and phone number of the “doctor,” according to Otero. Calls to the doctor, believed to have been Tatum, prevented officials from becoming immediately suspicious.

After not receiving written confirmation of Rudd’s illness, school officials visited the shelter where the girl was staying with her family. It was at that time they realized something was wrong. Her disappearance was only brought to the attention of police two weeks ago.

Tatum knew Rudd and her family through his work at the shelter, authorities say. Rudd’s mother had allowed her to spend time with Tatum, and her family did not report her missing.

Lanier would not say whether charges would be filed against Young.

“Right now our priority remains focused on Relisha,” said Lanier. “Charges for anyone down the road, we’ll talk about those when the time comes.”

The FBI and D.C. police cadets returned to D.C. General Hospital last week to search the grounds and speak with people who may have interacted with the family prior to the girl’s disappearance.

Relisha is described as a black female, 4 feet tall, and weighing approximately 70 to 80 pounds. She has black hair, brown eyes, and a medium complexion. Police say she may be in need of medication.

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