(Update: Exhumed body in Ala. could be notorious Bethesda slayings fugitive Brad Bishop)

Investigators probing the nearly 40-year-old case of Bradford Bishop — a one-time diplomat who has been missing since he was accused of killing his family in Bethesda in 1976 — want to exhume the body in Alabama of a man whose 1981 photograph resembles the notorious fugitive.

“We are running down every lead,” said Stephen Vogt, special agent in charge of the Baltimore field office of the Federal Bureau of Investigation.

Vogt declined to comment on the chances that the man is Bishop. But he said if it’s not, and Bishop is still alive and following news coverage of the latest development, Bishop should be careful.

“If he’s laughing at us, he shouldn’t laugh too long, because we’re coming after him,” Vogt said.

Bradford Bishop in the 1970s. (The Washington Post)

The identity of the man in the photograph has long been a mystery. On Oct. 18, 1981, he was walking down Highway 72 in Scottsboro, Ala., when a car hit and killed him, according to court filings. He had no identification and was assigned the name John Doe. A coroner took a photograph of the man before he was buried.

It is that photo that has investigators’ attention. The development was earlier reported by WRC (Channel 4).

“Both John Doe and Bishop have cleft chins, distinctive noses, thin lips and similar hairlines and sideburns,” wrote Pamela Hanson, an FBI agent in Alabama.

Her affidavit was filed Tuesday along with an exhumation request by Charles R. Rhodes, District Attorney for Jackson County, Alabama.

The tip about John Doe came after the airing of a recent CNN episode about the Bishop case on “The Hunt with John Walsh,” which produced numerous leads.

Authorities said if they are able to exhume the body they want to compare John Doe’s DNA to a sample of Bishop’s DNA, which was taken from evidence originally collected in the case.

Nearly four decades ago, when Bishop was a State Department Foreign Service officer, he unleashed a series of vicious attacks inside his Bethesda home, according to authorities. His mother, his wife and his three young sons — all beaten to death with a small sledgehammer.

While it was still dark, Bishop loaded the bodies into the family’s maroon Chevy station wagon, police say, drove 275 miles to a swampy and wooded part of North Carolina, dug a shallow grave and set the corpses on fire. Bishop’s station wagon was later found in North Carolina at the Great Smoky Mountains National Park [GSMNP] — some 207 miles from Scottsboro, Ala.

“Bishop was an avid outdoors man and had extensive camping experience in Africa and could have avoided being seen,” court records state. “The GSMNP encompasses 522,419 acres and has 850 miles of hiking trails. Bishop could have remained in the North Carolina/Tennessee/Alabama area for many years without being discovered.”

Hanson, the FBI agent, spoke with a funeral home director in Alabama who remembered John Doe’s body. He recalled that case as a hit and run, with the victim suffering multiple leg fractures. That could explain a slight different in height — measured 5’9” for John Doe compared to 6’1” for Bishop.

The funeral home worker also told Hanson he remembered removing clothing from John Doe and that “he was wearing multiple layers of dirty, heavy clothing, like he would expect a homeless person to wear.”

This story has been updated.