Background
This analysis is based on an older version of our inference model which is accurate but more difficult to read

Question

What was found in the crater in Khan Sheikhoun?

What caused the chemical calamity in Khan Sheikhoun on April 4, 2017?

Scenarios
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Calculated Conclusions
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Conclusions
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1

83%
Projectile north:

Remains of a surface to surface sarin projectile shot from the north.

83%

2

10%
Projectile other:

Remains of a surface to surface sarin projectile shot from the east, west or south.

10%

3

6%
IED:

Remains of a sarin improvised explosive device (IED).

6%

4

0.7%
Aerial sarin:

Remains of an aerial sarin bomb.

0.7%

5

0.2%
Unknown:

Remains of something other than a sarin bomb, projectile or IED.

0.2%
Implied plausibility
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Likelihoods based only on other elements of the analysis, not considering evidence of this sub-topic.
Projectile north

38%

Projectile other

20%

IED

19%

Aerial sarin

2.1%

Unknown

21%

Compatibility with evidence
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Likelihoods based only on evidence of this sub-topic, assuming all hypotheses equally plausible.
Projectile north

83%

Projectile other

10%

IED

6%

Aerial sarin

0.7%

Unknown

0.2%

Conclusion
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Final likelihoods, combining plausibility and evidence.
Projectile north

83%

Projectile other

10%

IED

6%

Aerial sarin

0.7%

Unknown

0.2%

Analysis

Evidence (9 items)

Eyewitnesses from the town claim that the chemical effects began near the crater site.

Sources: The Guardian
The crater in Khan Sheikhoun
The crater in Khan Sheikhoun
www.bellingcat.com
Projectile north

23%

Projectile other

23%

IED

23%

Aerial sarin

23%

Unknown

10%

Projectile north

23%

Projectile other

23%

IED

23%

Aerial sarin

23%

Unknown

10%

The crater site is in the northern part of Khan Sheikhoun
Projectile north

31%

Projectile other

13%

IED

19%

Aerial sarin

19%

Unknown

19%

Projectile north

31%

Projectile other

13%

IED

19%

Aerial sarin

19%

Unknown

19%

The only remains seen in the crater are what appear to be a flattened cylindrical metal piece with some green coloring and a flat circular component resembling a cap measuring 11 cm across.

Weapon remnants found in a crater in Khan Sheikhoun
Weapon remnants found in a crater in Khan Sheikhoun
www.almasdarnews.com
Projectile north

18%

Projectile other

18%

IED

32%

Aerial sarin

11%

Unknown

21%

Projectile north

18%

Projectile other

18%

IED

32%

Aerial sarin

11%

Unknown

21%

The metal piece found in the crater is bent facing south, with debris in the southern part of the crater.
Projectile north

29%

Projectile other

18%

IED

18%

Aerial sarin

18%

Unknown

18%

Projectile north

29%

Projectile other

18%

IED

18%

Aerial sarin

18%

Unknown

18%

Photos of the crater do not match the videos showing the alleged moment of the aerial attack.

Sources: Bellingcat
Alleged attack site
Alleged attack site
www.bellingcat.com
Projectile north

26%

Projectile other

26%

IED

26%

Aerial sarin

13%

Unknown

10%

Projectile north

26%

Projectile other

26%

IED

26%

Aerial sarin

13%

Unknown

10%

Early photos of the crater site from the April 4 show white residue or liquid around the crater not visible in later photos.

Early morning photo of the crater
Early morning photo of the crater
www.facebook.com
Projectile north

23%

Projectile other

23%

IED

23%

Aerial sarin

23%

Unknown

8%

Projectile north

23%

Projectile other

23%

IED

23%

Aerial sarin

23%

Unknown

8%

There is no visible damage in the area surrounding the crater.
Projectile north

21%

Projectile other

21%

IED

21%

Aerial sarin

21%

Unknown

18%

Projectile north

21%

Projectile other

21%

IED

21%

Aerial sarin

21%

Unknown

18%

UN-commissioned expert assessments of photographic and satellite image reported that the crater was most probably caused by a heavy object impacting the ground at high speed.
Sources: JIM Report
Projectile north

27%

Projectile other

27%

IED

6%

Aerial sarin

29%

Unknown

10%

Projectile north

27%

Projectile other

27%

IED

6%

Aerial sarin

29%

Unknown

10%

UN-commissioned expert forensic assessments reported that the remnants found in the crater belonged to a 300-500 mm munition.
Sources: JIM report
Projectile north

20%

Projectile other

20%

IED

20%

Aerial sarin

26%

Unknown

14%

Projectile north

20%

Projectile other

20%

IED

20%

Aerial sarin

26%

Unknown

14%

Discussion
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This topic is part of a broader analysis. To view the discussion page of the main analysis, click below:
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alwaysrinse

Jun 27, 2021 at 7:50 AM

Your priors on the aerial sarin bomb are very low. Why?

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Rootclaim

Oct 7, 2021 at 11:03 AM

The reasoning behind our numbers are explained in the “starting point” section.