Cartha “Deke” DeLoach, shown in 1978. (James K.W. Atherton/The Washington Post)

Cartha D. “Deke” DeLoach, who was the third-ranking official at the FBI under J. Edgar Hoover and briefed the president on the bureau’s activities in the late 1960s, died March 13 at a hospital in Hilton Head Island, S.C. He was 92.

His son Tom DeLoach confirmed the death but did not disclose a cause.

Mr. DeLoach spent 28 years at the Federal Bureau of Investigation and was the last surviving member of Hoover’s inner circle. He was, in many ways, the classic agent — a former college football player, a keeper of secrets and a Hoover loyalist to the end.

As assistant to the director, Mr. DeLoach led high-profile crime investigations, including the manhunt that led to the capture of the Rev. Martin Luther King Jr.’s assassin, but he had an ambiguous role in the bureau.

“On the positive side, he was very smart, he had an incredible memory and was totally well informed about the FBI and J. Edgar Hoover’s activities,” Ronald Kessler, author of “The Secrets of the FBI” and other books about the FBI, said in an interview. “On the negative side, he was used by Hoover to further Hoover’s agenda.”

Opponents sometimes thought of Mr. DeLoach as Hoover’s henchman, possessing salacious secrets that could silence the FBI’s enemies. In the 1960s, when the bureau engaged in surveillance of political figures and suspected dissidents, Mr. DeLoach was “a courier to the White House of the juicy gleanings from the FBI,” in the words of Time magazine.

Mr. DeLoach helped burnish the bureau’s public image throughout the 1960s. He negotiated a deal with Hollywood mogul Jack Warner for a network television series about the FBI and reviewed scripts. The ABC series “The F.B.I.” began in 1965 and ran for several years.

Mr. DeLoach delivered fiery anti-communist speeches, often had daily meetings with President Lyndon B. Johnson and, as early as 1965, was seen as the heir apparent to Hoover as director of the FBI.

But Hoover turned 70, then 75, and showed no interest in retiring from the job he had held since 1924. He was still serving as FBI director when he died at age 77 in 1972.

According to Mr. DeLoach’s son, his father turned down three offers to be director of the FBI — one by Johnson and two when Richard M. Nixon was president.

“Under President Nixon, Attorney General Richard Kleindienst made that offer twice,” Tom DeLoach said. “He found it easier to turn down an attorney general. It might have been different if the president had asked.”

Mr. DeLoach retired from the bureau in 1970, on his 50th birthday.

According to a syndicated column that year by Rowland Evans and Robert Novak, there was some relief within the FBI because of Mr. DeLoach’s perceived “right-wing bias and blatant opportunism.”

He then became a vice president of corporate affairs for Pepsi­Co but continued to consult occasionally with the FBI for years.

In the 1970s, Mr. DeLoach confirmed to The Washington Post the existence of the FBI’s domestic spying program. Among other things, the FBI had tapes of King’s bedroom encounters with women other than his wife. Sen. Henry M. Jackson (D-Wash.) called the revelations “outrageous” and said the FBI’s snooping “goes to the heart of the separation of powers.”

Several journalists said Mr. DeLoach had offered to reveal the tapes in an effort to discredit King in the 1960s, but Mr. De­Loach vigorously denied the charges. He said the FBI investigated King only to determine if the civil rights movement had been infiltrated by communists.

“Everything was initiated by Hoover,” Kessler said.

Nonetheless, when it came to old-fashioned crime fighting, few could find fault with Mr. De­Loach. He was instrumental in developing a nationwide computerized crime database, now known as National Crime Information Center, or NCIC.

He helped lead the FBI’s investigation of the killings of civil rights workers James Chaney, Andrew Goodman and Michael Schwerner in 1964. After King was assassinated in 1968, Mr. DeLoach personally directed the investigation that led to the arrest of James Earl Ray.

Cartha Dekle “Deke” DeLoach was born July 20, 1920, in Claxton, Ga. He was a child when his father died, and he was working in cotton and tobacco fields by the time he was 10.

He attended a junior college in Georgia, then won an athletic scholarship to Stetson University in Deland, Fla., where he was quarterback on the football team.

Soon after his graduation in 1942, he joined the FBI. He had assignments in Norfolk and Cleveland before serving in the Navy during World War II. He returned to the FBI in 1946 and was assigned to the Washington headquarters a year later.

He began working in 1953 with deputy director Clyde Tolson, the No. 2 official at the FBI and Hoover’s closest friend and confidant. Mr. DeLoach had jobs in the crime-records and communications divisions throughout the 1950s and had an office near Hoover’s.

In later interviews, Mr. De­Loach sometimes said Hoover considered him “the son he never had.”

Since 1985, Mr. DeLoach had lived in Hilton Head Island, where he was chairman of a banking company and the chief fundraiser for an arts center.

Survivors include his wife of 68 years, Barbara Owens De­Loach of Hilton Head; seven children, Barbie Lancaster of Bluffton, S.C., C.D. “Deke” De­Loach Jr. of Howey-in-the-Hills, Fla., Tom DeLoach of Columbia, S.C., Theresa DeLoach and Greg DeLoach, both of Hilton Head, Sharon Bleifeld of Alpharetta, Ga., and Mark DeLoach of West Palm Beach, Fla.; 13 grandchildren; and 16 great-grandchildren.

He published a book about his experiences, “Hoover’s FBI: The Inside Story by J. Edgar Hoover’s Trusted Lieutenant,” in 1995.

In the 1990s, allegations surfaced that Hoover — who often seemed curious about the sex lives of others — may have had a homosexual relationship with Tolson, who died in 1974.

In a 1993 interview on CNN’s “Larry King Live,” Mr. DeLoach refuted the accusations as “third-handed gossip, innuendo, lies, deceit” and “a pile of garbage.”