I'm Kelly McEvers and this is Embedded, an NPR podcast where we take a story from the news and go deep.

NavPreet Sasi is an ER doctor from Toronto. People call him Dr. Nav. A couple years ago he went on his first mission for Medeson San Frontier, MSF, also known as Doctors Without Borders.

These are these incredible people who are like the first ones to get there when there's a war, earthquake, outbreak of Ebola or a famine.

Dr. Nav was posted at a hospital in Yemen, right on the front line of Yemen's Civil War. One day he was working in the emergency room.

I was rounding, I was doing my rounds, dealing rounds in the hospital and seeing patients.

And while that was happening, there was sort of heavy fighting going on outside.

And then this happened.

There was sort of a really loud, really loud to the boom.

And I actually, my sort of my initial thought was, whoa, something had just kind of hit like just outside us.

What I didn't realize was that there was actually all this glass that had cracked just to the window that was not too far from me, we had 10-15 feet to my right.

A mortar had hit the hospital. It broke that glass window.

When I looked behind me, there was smoke everywhere. And then, like, in those situations, everything kind of goes really slowly.

Nav eventually gets himself together, runs to a safe room at the back of the hospital.

He says MSF was not the target of this mortar. It was an accident.

This is what's been happening to a lot of MSF hospitals all around the world.

Another Med San San Frontier hospital has been leveled by air strikes this time.

Doctors without borders said that their hospital was partially destroyed by barrel bombs.

Yes, I say Stadley attacks appear to have been deliberate.

It says 27 people were killed in an air strike that one killed at least 23 people.

And when these attacks happen, sometimes, of course, the hospital has to close.

And then all the people in these places, if Afghanistan, Central African Republic, South Sudan, Syria,

will now have no access to health care. They basically lose their life line.

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