PORT GIBSON, Miss. -- The FBI said Friday 30 investigators in Mississippi are looking into the death of a black man who was found hanging from a tree.

It might be suicide, but it's the possibility of lynching that has the U.S. Justice Department involved.

Otis Byrd CBS News

Police tape deep in the woods of Port Gibson marks the area where 54 -year-old Otis James Byrd was found hanging by a bedsheet from one of the trees on Thursday.

Don Alway, the special agent in charge of the FBI's Jackson office, said investigators still don't know how he got there.

"Everyone wants answers, and they want those quickly -- we understand that," Alway said. "We are going to hold off on coming to any conclusions until the facts take us to a definitive answer."

Police tell CBS News Byrd was found about 500 yards from his home. He was two feet off the ground, a skullcap halfway over his head. There were no obvious signs of trauma.

Police tape marks off the area where 54-year-old Otis James Byrd was found hanging from a tree on March 19, 2015, near Port Gibson, Mississippi. CBS News

"It wasn't no chair, no ladder," Claiborne County Sheriff Marvin Lucas said, adding that it didn't appear Byrd had stood on something or had been restrained.

It was Lucas who called in the FBI.

"We all know the history of Mississippi, and I don't want anyone to feel like I got anything to hide," Lucas said.

As word spread, so did concerns -- and pleas from Byrd's family.

"Please, for the closure of this family, just come and say something," nephew Lekendrick Byrd asked.

His family reported Byrd missing two weeks ago. He was an ex-con, convicted of murder in 1980 and paroled in 2006.

"We're still trying to find out more about Mr. Byrd's life," Alway said. "We're really trying to paint a picture of what was going , both personally and professionally."

Evidence recovered from the area close to where Byrd's body was found is now at the state crime lab. Investigators are hoping to learn more next week when an autopsy is complete.