They were cremated and the ash disposed of.
So there we have a prime example of 'holocaust doublespeak'.
When it's convenient they say the evidence was destroyed, but then they contradict themselves by telling the gullible that tons of Jew human remains are right in front of their eyes.
Now, a little smoke & mirrors:
"alleged ash pond at Auschwitz"
"dried up ash pond at Auschwitz"
"Markers for the Krema III ash pond"
"Ash pond for Krema II at Birkenau"
So where are excavations and verification that there are ashes of Jews at Auschwitz?
This is too easy.
So called "holocaust eyewitnesses" making absurd, impossible, and contradictory claims is not the exception, but the rule.
Revisionists are just the messengers, the absurd impossibility of the laughable 'holocaust' storyline is the message.