Matt Rourke, Associated Press
Presidential hopeful Sen. Hillary Clinton greets rally participants in Blue Bell, Pa., on Monday.

BLUE BELL, Pa. — As part of her argument that she has the best experience and instincts to deal with a sudden crisis as president, Sen. Hillary Rodham Clinton recently offered a vivid description of having to run across a tarmac to avoid sniper fire after landing in Bosnia as first lady in 1996.

Yet on Monday, Clinton admitted that she "misspoke" about the episode — a concession that came after CBS News showed footage of her walking calmly across the tarmac with her daughter, Chelsea, and being greeted by dignitaries and a child.

The backpedaling was a rare instance of Clinton acknowledging an error, and she did so on a sensitive issue: She has cited her "strength and experience" since the start of the presidential race, framing her 80 trips abroad as first lady as preparation for dealing with foreign affairs as president. That argument was behind her campaign's "red phone" commercial, which cast her as best able to handle a crisis.

Clinton corrected herself at a meeting with the Philadelphia Daily News editorial board; she did not explain why she had misspoken, but only admitted it and then offered a less dramatic description.

Clinton said she had been told "that we had to land a certain way and move quickly because of the threat of sniper fire," not that actual shots were being fired.

"So I misspoke," she said.

Earlier Monday, Clinton advisers corrected the Bosnia anecdote, saying they did not want it to harm her credibility. One Clinton foreign adviser, speaking on condition of anonymity in exchange for being candid about her mistake, said that Clinton had been "too loose" with her words and that she risked looking like "she was trying to pump up a somewhat risky situation into a very dangerous one."

In her most recent account, offered last week, Clinton described an action-packed arrival in war-torn Bosnia.

"I certainly do remember that trip to Bosnia," she said, in remarks that aides described Monday as not being part of her prepared speech. "I remember landing under sniper fire. There was supposed to be some kind of a greeting ceremony at the airport, but instead we just ran with our heads down to get into the vehicles to get to our base."

In interviews Monday, aides to Clinton at the time of the trip, as well as an Associated Press photographer who was on the trip, said that she and others were briefed before landing about the possibility of sniper fire around the airport in Tuzla, Bosnia.

None of the aides remember actual sniper fire, nor did the photographer, Doug Mills, who now works for The New York Times.

"I remember being told we were going into a war zone, but I don't remember any commotion at the airport," Mills said. "I don't recall her running to cars. If that had happened, we would have made a picture of it."

Maj. Gen. William Nash, who has since retired but was then the commander of U.S. troops in Bosnia and was at the Tuzla airport that day, said in an interview that there was no threat of sniper fire at the airport during Clinton's visit. He said she was gracious during her visit and took pictures with the soldiers.

"She never had her head down," Nash said. "There was no sniper threat that I know of."

Before Clinton's admission that she had misspoken, a spokesman for the campaign, Howard Wolfson, was asked Monday on a conference call with reporters to square her recent accounts with other evidence. In response, Wolfson referred to news accounts at the time that described the region as hostile.

He then added: "There is no question if you look at contemporaneous accounts that she was going to a potential combat zone, that she was on the front lines."

Minutes later, when pressed to clarify his comment, Wolfson said news accounts made clear that the area in which she was landing was "a potential combat zone and was hazardous."

He said that in her memoir, "Living History," Clinton wrote about sniper fire in the hills and "clearly meant to say that" when she brought it up last week. He said she had described the event many times the same way and that "in one instance, she said it slightly differently."

In her comments Monday, Clinton made a similar point, saying, "I didn't say that in my book or other times." Clinton had described the sniper fire in similar terms at least twice in recent weeks. She mentioned it on Feb. 29 in Waco, Texas, when she was rolling out her "red phone" commercial, recalling the trip to Bosnia and saying that the welcoming ceremony "had to be moved inside because of sniper fire."

According to Clinton's public schedule for March 25, 1996, she arrived in Tuzla at 8:55 a.m. local time, and was greeted by the acting president of Bosnia, Ejup Ganic; the U.S. ambassador, John Menzies; two senior U.S. military officials; an 8-year-old girl; and a seventh-grade class that had been "adopted by Germany."

The first lady's public schedule, which was among more than 11,000 pages released by the National Archives last week, lists the greeting ceremony on the tarmac at the Tuzla airport this way: "Ambassador Menzies intros HRC to greeters; 8-year-old Bosnian Girl Reads Poem to HRC; HRC greets 7th grade class."

Later that day, Clinton spoke as at a show for approximately 500 troops. She was joined by the comedian Sinbad and the singer Sheryl Crow, both of whom performed for the troops, according to the schedule. Late that afternoon, Clinton and her entourage left Tuzla for Aviano Air Base in Italy.

Sinbad challenged her account of sniper fire soon after he heard it more than a week ago, saying the scariest part of the trip for him was wondering where the next meal would come from. Sinbad is supporting Sen. Barack Obama for president.