(CNN) -- Authorities have found what they believe to be the remains of Breeann Rodriguez, a 3-year-old Missouri girl whose neighbor told police he had suffocated the girl with a plastic bag and then tossed her from a highway.
A Missouri State Highway Patrol officer found the remains Tuesday evening along a ditch northeast of Hornersville, Missouri, about 8 to 10 miles from the girl's home in Senath, said Dunklin County Prosecuting Attorney Stephen Sokoloff said.
He said the remains are expected to be sent for forensic examination on Wednesday.
In a statement, Dunklin County Sheriff Bob Holder thanked the community for its assistance.
"We are saddened to confirm our fears, but glad we are able to recover her remains for her parents," Holder said.
Earlier Tuesday, 43-year-old Shawn Morgan of Senath appeared in court. He has been charged with first-degree murder in connection with Breeann's death.
Breeann was last seen on August 6, riding her pink bicycle with her brother outside their home.
Morgan does not yet have an attorney. The August 30 court appearance will be a counsel status hearing, the prosecutor's office said Tuesday.
According to a probable cause affidavit dated Saturday, police interviewed Morgan on Friday at the police department in Kennett, a larger community about 10 miles northeast of Senath.
The suspect said that he spotted the girl standing on a ladder by the pool in his backyard. He told police that he grabbed the girl and carried her inside his house.
There, according to the affidavit, the man "suffocated the girl with a white plastic trash bag, by holding it over her face and mouth.
"Morgan states that he felt like it took an hour for the girl to die," the document adds.
It says Morgan told police he put the girl's body into the same trash bag, and then drove to Missouri's Highway 164 and got rid of the body by throwing it over a railing into a floodway ditch.
After returning home, Morgan said, he then dismantled the girl's bike and dumped it into another, related waterway, the document says.
A bicycle was recovered there and identified by Edgar Rodriguez as belonging to Breeann, his daughter. Police said last week that they had found two training wheels similar to those on the girl's bike.
In addition to murder, Sokoloff said in a statement Saturday that Morgan is charged with armed criminal action and tampering with physical evidence.
The suspect, who Sokoloff said has three children of his own, is being held at the Dunklin County Justice Center.
