AMNA NAWAZ: For more on this, we turn to Sean Carroll.

He's the president and CEO of Anera.

That's a nonprofit helping refugees in the Middle East.

For the last six months, they have been delivering medicine, water and food in Gaza, including some 150,000 meals a day.

Sean, I just want to begin with your reaction to this news.

What did you think when you heard about the killing of these World Central Kitchen aid workers?

SEAN CARROLL, President and CEO, Anera: I thought, no, this can't be.

How can this be?

This can't be.

This can't be explained.

It can't be, and then devastation.

World Central Kitchen are -- is a partner.

They're colleagues.

They're friends.

The people who were killed are people that our team in Gaza work with.

So this was devastating, devastating news.

AMNA NAWAZ: And we should say too, you and your team know this loss.

Last month, you lost one of your team members, Mousa Shawwa, your logistics coordinator in Gaza.

He was killed in an Israeli airstrike after sheltering with his family in Deir al Balah, after he'd been out distributing aid.

We are so sorry for your loss.

But I have to ask, do you believe it's possible for aid workers to work safely in Gaza right now?

SEAN CARROLL: Well, look, we have made a decision to pause our work.

And that's not a decision we came to lightly.

Our Palestinian staff who live in the communities, who work in the communities that are from and live in, they have never really had safety, but they kept going, and now this level of depravity and inexplicable killing.

And I know there are questions and debates about whether it was intentional or unintentional.

I think we need to ask ourselves, is one better than the other?

If this was unintentional, how could this happen?

This was a clearly marked humanitarian aid convoy of three cars with World Central Kitchen logo and lettering clearly displayed.

So how could it be an accident?

And the evidence we have seen so far and what I have heard from our colleagues at World Central Kitchen suggested that it wasn't an accident, it was intentional.

AMNA NAWAZ: Well, let me ask you about that, because Israeli Prime Minister Benjamin Netanyahu has, in fact, said it was an unintentional strike, that it was what he called a tragic accident.

I know you cited some of the evidence why you believe it wasn't, but why do you believe Israel would target humanitarian aid workers?

SEAN CARROLL: You know, I don't know.

I think that's the question we all have to ask.

And I think Israeli society and the Israeli government and the Israeli military need to ask themselves as well, is this contributing to making Israel and Israelis safer?

I don't see how it could be.

So after the first reaction of shock and despair, the next reaction is, how could this be?

It doesn't make any sense.

I can't make any sense of it.

How would this be serving any objectives that make sense for anybody, for any side of this conflict?

AMNA NAWAZ: Netanyahu has also pledged a thorough investigation.

U.S. officials have said today they hope it will be swift and that the findings will be made public.

Do you have faith that the Israeli government can investigate its own forces in this case?

SEAN CARROLL: When an investigation is needed, the parties to the conflict, to the accident, to the incident, to the subject being investigated are not the best investigators.

We should have an independent investigation.

We would like to have it for our co-worker Mousa Shawwa, who was killed just under a month ago.

We still don't have an explanation on that killing.

This is an absolute minimum requirement, certainly for World Central Kitchen, and -- but for all of us, because we're wondering, are we next?

AMNA NAWAZ: Sean, have you had communications directly with Israeli officials about the safety of your team on the ground in Gaza?

SEAN CARROLL: Sure.

We communicate all the time.

We have to deconflict the areas we work, the shelters where our staff and their families are staying, where our staff are sheltering, our distribution centers, our cars.

That all has to be deconflicted.

We share the coordinates, the map coordinates of those.

And we check in.

We check in with them to verify or they check in with us?

But we had a check-in from them four days before Mousa Shawwa was killed in an airstrike.

And that and this World Central Kitchen killing now is -- makes us worried.

It makes us feel like it's not working.

AMNA NAWAZ: When you say it's not working, to be clear, you're saying you are in constant contact, groups on the ground are informing Israeli officials about your location and your coordinates,there's no way you see Israeli officials would not have known these were aid workers?

Is that what you're saying?

SEAN CARROLL: I mean, that certainly looks like the case with the World Central Kitchen, very clearly marked cars in a three-car convoy.

And this is something that's been an issue among many international NGOs throughout the course of this war.

And the deconfliction is actually done with the military, with the IDF.

And so the conversations and the communications feel like they're genuine, that we're all doing the right thing, and we're deconflicting, and we're getting things put into the system.

But if people are killed, when they shouldn't be, then, obviously, we end up questioning whether this is working.

And it doesn't seem to be working.

AMNA NAWAZ: And what has been the response from Israeli officials when you raise those concerns?

SEAN CARROLL: Well, we don't -- we'd like a response on the death of our colleague.

We don't have any response.

There seemed to be interest initially when they mistakenly thought he was an American citizen.

That interest seemed to lessen when we said he didn't have a U.S. passport.

He's a Palestinian.

We don't have a response yet.

I hope we will get a response.

And I'm sure World Central Kitchen is very much going to be demanding an explanation for the death of their staff.

AMNA NAWAZ: That is Sean Carroll, president and CEO of Anera, a nonprofit helping people in Gaza, suspending operations for now.

Mr. Carroll, thank you for your time.

SEAN CARROLL: Thank you for having me.