Eric Engberg, a former political and investigative reporter for CBS News who also covered overseas conflicts and won electronic journalism’s top honor for a report identifying a Vietnam veteran buried in the Tomb of the Unknowns, has died. He was 74. Engberg died Sunday in his sleep at his home in Palmetto, FL, where he retired.

“One of the best television correspondents of his generation,” former longtime CBS newsman Dan Rather said today. He called Engberg “tough but fair, and that rarity: a hard-nosed reporter with a sense of humor.”

Engberg made news last year from retirement. In February 2015, questions arose cbs_news_logoabout Bill O’Reilly’s claim of reporting from a dangerous war zone during the Falklands War in 1982. Engberg had been with O’Reilly, then a CBS News correspondent, and other reporters who were prevented from reaching the front and were contained in Buenos Aires, where there was street violence. “It was not a war zone or even close. It was an ‘expense account zone,'” Engberg said of O’Reilly’s time in the Argentine capital covering the war. O’Reilly blasted back, calling Engberg “Room Service Eric”; Engberg responded with a video.

Born on September 18, 1941, in Highland Park, IL, Engberg appeared on CBS Evening News for nearly three decades. He joined the division’s New York bureau in 1975 as a correspondent and was sent to the Dallas bureau the next year. He joined the Washington bureau in 1981, where he remained until his retirement in 2002. Before joining CBS News, Engberg got one of the biggest scoops of his career when he reported the resignation of Vice President Spiro Agnew in a Baltimore courtroom in 1973.

He might be best remembered for Reality Check, a series of original segments on the federal government that ran on the broadcast network in the 1990s. It launched as a regular segment on the accuracy of charges and countercharges flung about in the 1992 presidential campaign and grew from there. Among his most memorable reports were those about expensive bodyguard units created to protect cabinet secretaries, an $18 million luxury subway built to carry U.S. senators a few hundred yards to their offices and an unnoticed law revision allowing U.S. representatives to buy radio ads with taxpayer money.

He and his team won a Columbia University DuPont Silver Baton for a Reality Check investigation that made big news in January 1998. Engberg’s reports built a case identifying an unknown soldier in Arlington National Cemetery as U.S.A.F. 1st Lt. Michael Blassie, a pilot shot down during the Vietnam war. The investigation resulted in the exhumation of the body, a positive DNA identification and a reburial.

During his CBS News career, Engberg was the first to report the existence of a security fence at the home of White House aide Oliver North paid for with Iran-Contra money and among the first to link faulty O-rings to the explosion that brought down the Space Shuttle Challenger in 1986. Engberg also covered many presidential election campaigns, including Bob Dole in 1976, Gary Hart and Geraldine Ferraro in 1984, George H.W. Bush in 1988 and Patrick Buchanan in 1992. Engberg was also sent overseas to report on the IRA hunger strikes in Northern Ireland, the aftermath of the Tiananmen Square uprising in Beijing and the fall of the Berlin Wall.