Sienna Miller narrowly avoided ISIS bombing while on humanitarian mission

Actress Sienna Miller has been an ambassador for the International Medical Corps (IMC) for the past six years. Last summer she made a humanitarian trip to help Syrian refugees in Lebanon, and she says it could have cost her her life.

"On our second morning we drove the so-called road to Damascus, heading just a few miles from the Syrian border to visit a settlement with a few thousand refugees," she told FOX411 at the ICM Annual Awards Ceremony in Beverly Hills on Thursday. "About two hours into the drive, the vehicle ahead of us in a convoy suddenly stopped and pulled over. Colin, our country director, got out and informed us precisely and without emotion that a bomb had just exploded at a checkpoint we had just passed minutes earlier."

Miller said there were several fatalities, and they were forced to cut short their trip and head back to Beirut on another route.

"In the hours that ensued, we discovered that the bomb was part of a larger assassination plot by the members of ISIS to kill Lebanese police, security and parliamentary officials in the area," she continued. "We were all shaken by the experience. Partly because it could have been us if we'd taken a little longer at breakfast or stopped off for coffee along the way. But more importantly, because this was not uncommon. This wasn't rare."

Miller's said her Lebanon scare wasn't her first. In 2009, the screen star came face-to-face with rebels in the Eastern Congo, where she was stopped by 13-year-olds wielding Kalashnikov rifles before she sat down with corrupt town leaders to discuss the epidemic of sexual violence against women and children in the area.

"It was the furthest I had been from the world I knew or understood," Miller recalled. "As a woman and an outsider, I felt in danger... But I get to go in and leave. I get to go home to a routine in which the overwhelming suffering is background noise on TV."

As Miller pointed out, those healthcare professionals and first responders don't get to walk away after just a few days on the ground. They spend weeks, months, even years amid deplorable conditions - risking their own lives for people they've often never met.

"It's a reminder of what we take care for granted," Miller said.

IMC has had a base in Lebanon since 2006, offering sanitation, health care, water and medical services for those displaced by the wars in Syria and Iraq. The non-profit organization has acted as first responders in almost every major humanitarian crisis globally for the past 30 years. IMC is currently dealing with both the Syrian conflict and West Africa Ebola outbreak, operating a 70-bed Ebola Treatment Unit  in Liberia and working to open another in Sierra Leone while also delivering lifesaving personal protective equipment and training local health workers to mitigate their risk of infection.

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