This story was updated at 5:16 p.m. on Wednesday, Nov. 20, to include additional details.
Multiple agencies, including the Tennessee Bureau of Investigation, were working a missing person investigation Wednesday in Nickajack Lake.
Investigators "developed information" that has led them to believe the body of 29-year-old Matthew Henry could be in the lake, according to the 12th Judicial District Attorney's Office.
Henry, of Dunlap, Tennessee, was reported missing in April 2018, and officials have said they suspect foul play and are treating the case as a homicide.
Dunlap police have met with more 200 people concerning Henry's disappearance, with more than 50 being formally interviewed, police Chief Clint Huth has said.
While officials haven't released many details of what they believe happened to Henry, they have said they've narrowed the scope of the investigation. And the public's help has played a major role in that.
Henry was last seen in a convenience store on State Route 28 on the south end of downtown Dunlap on the morning of April 15, 2018. His vehicle, a white convertible Ford Mustang, was recovered across the road from the convenience store in the parking lot of the local Tractor Supply.
Since then, the TBI and FBI have joined the investigation, the Times Free Press previously reported.
The FBI has also had a role in the investigation, the Times Free Press has previously reported.
Currently, the TBI and sheriff's offices in Marion and Hamilton counties are assisting Sequatchie County in the search, District Attorney Mike Taylor said.
The Tennessee Valley Authority is also assisting by shutting down some turbines to allow for the underwater search, Taylor said.