PRESCOTT, Ariz. (AP) — Even while being held hostage by Islamic State extremists, Kayla Mueller's family and friends say she tried to find the good in everything.

A portrait of the 26-year-old humanitarian aid worker from Prescott, Arizona, came as her death was confirmed by the U.S. government. Family members spoke fondly of her free spirit and efforts to ease the suffering of others as a small memorial of flowers and handwritten notes took shape in her hometown near a sign calling on people to "Pray for Kayla."

Mueller was captured in August 2013 in Syria, but her captivity had largely been kept secret in an effort to save her. President Barack Obama said a military operation last summer to recover Mueller and others failed when rescuers arrived only "a day or two" after the group had been moved.

Few details are known about Mueller's time in captivity and how she died. The Islamic State group claimed Friday that Mueller was killed in a recent Jordanian airstrike targeting the militants. The Pentagon said Tuesday that it doesn't know how she died but is certain it was not during the airstrike.

Family members released a letter an imprisoned Mueller wrote last year in which said she was staying strong and praying.

"I have come to see that there is good in every situation, sometimes we just have to look for it," a captive Mueller wrote.

During a press conference Tuesday outside Prescott's historic courthouse, family and friends remembered Mueller and said that even in the worst circumstances, she focused on the positive. They said she taught her guards to do crafts and make peace birds out of paper. And she stood on her head for exercise in her cramped quarters.

Beyond those few details, family members have not said what life was like for Mueller in captivity, including whether she was tortured. Three other Americans — journalists James Foley and Steven Sotloff and aid worker Peter Kassig — were beheaded by Islamic State militants last year.

Arizona Sen. John McCain and Rep. Paul Gosar, a Republican who represents Prescott, were in close contact with Mueller's family and government officials throughout her captivity.

Gosar told The Arizona Republic that one effort to free Mueller involved a man who traveled to the Syrian prison camp where Mueller was being held. The man told the captors he was Mueller's husband in a ruse designed to free her, Gosar said, but it didn't work.

In addition, Gosar's office said the name of Aafia Siddiqui, a Pakistani scientist convicted of shooting at two U.S. soldiers in Afghanistan, came up in discussions with Islamic State militants over Mueller. Siddiqui is an American-educated woman whose release has long been sought by terrorists.

In Mueller's hometown, residents began to honor her. Her family has encouraged people to donate to organizations Mueller would have supported, saying big displays of support wouldn't mesh with her humble nature.

Mueller's aunt, Lori Lyon, said her niece touched the hearts of people around the world who want to be more like the globe-trotting aid worker.

"And if that is her legacy and the footprint that she leaves on the world," Lyon added, dissolving into tears, "then that is a wonderful thing."

From Prescott, she helped raise awareness of HIV and AIDS and offered comfort at a women's shelter. In Flagstaff, where she attended college, she protested genocide in Darfur. Her desire to help others stretched beyond Arizona to Palestinian territories, Israel, India, France and Syria.

"I'm not sure yet how to live in a world without Kayla, but I do know that we're all living in a better world because of her," a tearful Eryn Street, a close friend of Mueller's said from the Prescott courthouse plaza.

In 2010, Mueller spent time with the International Solidarity Movement, a group of foreign activists who come to the West Bank and east Jerusalem to show support for the Palestinians. Activists frequently participate in West Bank protests against Israel's separation barrier, and organizer Abdullah Abu Rahmeh said a protest Friday would be dedicated to Mueller.

"We were shocked to know that Kayla was taken hostage, and we were shocked more when she was killed because she came here to help people," Abu Rahmeh said.

Obama pledged to bring Mueller's captors to justice "no matter how long it takes." The White House said the president had spoken with Mueller's parents and offered prayers. From Jordan, government spokesman Mohammed al-Momani offered his country's condolences.

Mueller wrote passionately about conditions in war-torn Syria, where she had gone to help refugees. In a blog post, she wrote: "Every human should act. They should stop this violence."

Her family and friends told of simple things Mueller did, such as such as giving people food and water, and searching for clothing and housing. Street recalled the two of them making the best of their car breaking down about a half-mile from Street's home. Getting the car towed would be no fun, she said.

"Instead, we turned on Bob Marley on full blast on the radio and, with the car in neutral, we started pushing that golden brown chariot home," she said.

Prescott, a mountain town that resembles a relic of the Old West in many ways, only recently begun to recover from the deaths of 19 elite firefighters who died in 2013 in a wildfire in the deadliest single day for firefighters since Sept. 11, 2011.

"What a fine, fine woman and a tribute to Prescott," resident Tina Nemeth said. "It's just so sad, it really is, and everyone feels exactly the same. It's a shock it hit Prescott. We're not that big of a town."

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