President Ronald Reagan carried a handgun with him at all times during his years in office, author Brad Meltzer writes in the New York Daily News.

Meltzer says he was doing research for his latest thriller "The President's Shadow," and wanted to talk to Secret Service agents about how the president lives.

At Secret Service headquarters he was taken to a small museum area where he saw such items as a newspaper marking John F. Kennedy's assassination and the actual door from the limousine Reagan was getting into when he was shot by John Hinckley Jr.

"It was an eerie keepsake for sure," Meltzer writes. "But not nearly as eerie as the next detail they told me. We were talking about Reagan and that day he was shot. Then one of the agents offered this secret: When Reagan was president, he carried his own gun."

Reagan carried the .38-caliber in his briefcase, and even took it onto Air Force One, Meltzer was told.

Meltzer didn't say whether Reagan was already carrying the gun when Hinckley shot him on March 30, 1981, just 69 days after his inauguration or whether it was the shooting that inspired him to carry the gun.

"Whatever you think of Reagan, you have to admit, he had a black belt in badassery," Meltzer wrote.

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