ATLANTA (AP) -- An employee for the Centers for Disease Control and Prevention who was reported missing more than six weeks ago was found drowned in a river, with no sign of foul play, authorities said Thursday.

Timothy Cunningham's body was found Tuesday partially submerged in water and mud on the west bank of the Chattahoochee River in northwest Atlanta, fire-rescue department spokesman Sgt. Cortez Stafford said at a news conference.

Fulton County Chief Medical Examiner Jan Gorniak determined the cause of death. "Since the investigation is ongoing, we do not have ... whether it was an accident, a suicide, or anything other than that" Cunningham drowned, Gorniak said.

A fisherman first discovered Cunningham's body and called authorities, said Stafford, who noted the body was found in an area that authorities had already searched in February without finding anything.

Cunningham, 35, was an epidemiologist at the Atlanta-based federal agency. He disappeared Feb. 12. His family reported him missing on Feb. 16 after going to his home and finding his belongings and vehicle there.

Police previously had said they had no evidence of foul play but couldn't rule it out. The civilian group Crime Stoppers offered a reward of up to $15,000 for information pointing to any criminal activity.

CDC officials said previously that reports Cunningham had been passed over for a promotion were incorrect. In a statement, the CDC said Cunningham received an "exceptional proficiency promotion" July 1 to the position of commander, an early promotion reflecting his excellence as an employee.

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