A 9-year-old girl who was reported missing from an Indiana trailer park on on Friday was found dead tonight, and a man described as a neighbor and family friend was charged with murder, police said.

Allen County Sheriff Ken Fries said Aliahna Lemmon's body was found after 9 p.m. today, and investigators believe she was killed on Friday, the same day she was reported missing.

The girl and her two sisters had been staying in the Northway mobile home park in Fort Wayne with Mike Plumadore, 39, a family friend, while their mother was sick.

Plumadore reported the girl missing Friday night. Police said he told them that he last saw her early Friday morning, and when he first realized that she was no longer in his mobile home, he assumed that she had gone home to her mother.

Plumadore has been charged with murder and is expected to appear in court Tuesday morning, sheriff's spokesman Cpl. Jeremy Tinkel told The Associated Press.

Fries did not say specifically where the girl's remains were found, but sources told ABC affiliate WPTA-TV in Fort Wayne that there was crime-scene tape around a dumpster and around Plumadore's home.

Plumadore was arrested after his third interview with police, when he gave "indication as to his involvement in this," and where the body could be found, Fries told WPTA.

Fries said Plumadore has a criminal record in North Carolina and Florida.

The tragic discovery came the same day that police announced that the FBI had joined the investigation and candlelight vigil was being held for Aliahna in Fort Wayne.

A page had been set up on Facebook for the missing girl called "Find Aliahna Marie Maroney Lemmon Missing from Fort Wayne, Indiana."  On Sunday, the group posted, "Merry Christmas Aliahna where ever you are! We won't give up on you!"

"No kid should be missing Christmas!" the post read.

ABC News affiliate  INC Now contributed to this report.