Last month, a group of people gathered in Kabul at the upscale Kabul Health Club for a fundraiser organized by a 36-year-old British surgeon named Karen Woo.

The young blond doctor wanted to raise money for a medical expedition to the remote, mountainous Nuristan province of Afghanistan, where she was headed as a member of an 11-person medical team.

The trip was the culmination of Woo's longstanding advocacy for Afghan causes.

Woo knew that the medical expedition by foot and packhorse to the remote Nuristan province would not be easy but she was undeterred.

“She was warned that it is dangerous there but she and her group took the risk to save other people's lives and went,” Mina Sherzoy, an Afghan-American womens’ activist told me by phone from Kabul. Sherzoy had worked with Woo the previous year when Woo helped organize a fashion show in London that included designs from the Afghan women’s sewing cooperative, established by Sherzoy.

As the medical team headed back to Kabul from Nuristan, insurgents robbed and killed the group, lining them up and shooting them, execution-style. The team—comprised of a Brit, a German, six Americans, and three Afghans—had been traveling without armed guards. The lone survivor, an Afghan driver, told authorities he was spared because he recited the Koran.

“I am just devastated since I have heard about Karen's death. She worked so hard to raise money to take medical supplies to Nuristan,” said Sherzoy, who had been working with Woo to plan another fashion show benefit for October. “Where is justice?”

Afghan officials have called the ambush a robbery. But the Taliban and Hizb-e-Islami, a terrorist group known to operate in northern Afghanistan, have claimed responsibility. Taliban spokesman Zabiullah Mujahid told the Guardian that the victims were spies and preachers, claiming they had Bibles in Dari and maps of Taliban locations in northern Afghanistan as part of the International Assistance Mission (IAM), an active Christian non-profit in Afghanistan since 1966.

In a statement, Woo’s family denied the Taliban allegations that she was a Christian missionary. “Her motivation was purely humanitarian. She was a Humanist and had no religious or political agenda,” the statement read. “She wanted the world to know there was more than a war going on in Afghanistan, that people were not getting their basic needs met. She wanted the ordinary people of Afghanistan, especially the women and children, to be able to receive health care.”

Woo had known that the medical expedition by foot and packhorse to the remote Nuristan province would not be easy but she was undeterred.

“We will begin at about 7,000 feet, ascend to almost 16,000 feet before dropping down to around 9,500 feet for our final destination,” she wrote in a June 30 email to friends, soliciting donations for the mission. “The total walking distance will be 120 miles round trip. The effort is worth it in order to assist those that need it most.”

Photojournalist Kate Brooks, who frequently works in Afghanistan, met Woo in Kabul shortly before Woo and the other aid workers departed for the fatal mission to Nuristan.

“She was talking about getting physically fit and brushing up on maternal health care,” said Brooks, who was impressed by her passion. “She was graceful, yet had a strong personality and was full of life.”

Woo, who grew up in Hertfordshire, U.K., worked five years as a general surgeon in Australia, London, Papua New Guinea, South Africa, Trinidad, and Tobago before joining the private medical firm Bupa in November 2008. Her friend Kim Sengupta wrote in the Independent that Woo became passionate about the plight of the Afghan people after visiting a friend in Kabul in 2008.

In late 2009 Woo left Bupa to work full-time in Afghanistan, and her lighthearted blog, Explorer Kitten, painted her transition to life and work in Afghanistan. “I'm now slowly morphing out of my London life, no sexy dresses and high heels here; I find myself blending in with the blokes,” she wrote.

Woo, who was to marry in London soon, detailed her travails locating silk for a ball gown in Kabul (she eventually found fabric at her friend Mina’s cooperative), and the pros and cons of wearing and bringing nail polish on her Nuristan mission. “Ridiculous I know but several tense minutes were spent thinking through the consequences of bonding with the women of the village over Crimson Lake or Buttercup Baby, only to find that nail polish is considered to be the devil's sporn … and that my actions are punishable by death.”

In anticipation of the journey, Woo wrote of her fear—not of the Taliban, but of her ability to practice medicine in the difficult environment. “The trek scares the living daylights out of me right now, what if I'm not good enough? Expedition medicine yes, in theory, in some strange ways it's the game I've been playing all my life in various ways.”

Woo was accompanied by an accomplished and able team led by Dr. Tom Little, an optometrist from New York state who was affiliated with the International Assistance Mission. Little and his family had lived through the Russian occupation and civil war in Afghanistan before being expelled in 2001 during a Taliban crackdown on Christian aid organizations.

Little spoke fluent Dari and was beloved by Afghans for his kindness and decades of service providing health care for the Afghan people. “He was like a father to me,” a young Afghan woman told me, asking me to keep her name a secret for fear of retribution. She had seen Little two days before he left. "He gave me my contact lenses supply for a year. I told him that day that he has done a lot for me and I had never done anything for him."

In a 2003 interview with NPR, Little spoke about why he refused to leave Afghanistan. “We've come here to identify in some small sense with the Afghan people. And, for us, at those periods just to leave and when they are not able to leave just because we're afraid, it seemed dishonest and shameful almost to say goodbye to our friends and patients here who couldn't leave.”

Elise Jordan is a New York-based writer who frequently travels to Afghanistan. She served as a director for communications in the National Security Council from 2008-09 and was a speechwriter for Secretary of State Condoleezza Rice.