Yea, there are probably many trapped inside the building. Even if the building survived, many are buried in tons of mud. And if the building was obliterated, the bodies washed downstream to Nepal and maybe even India. With all the rolling and debris, the bodies are likely dismembered.
And we have siao langs in this thread shouting "confirmed death counts from that side too low! Cover up! Ccp is ccb! "
This kind of situation very hard to confirm death count since you need to access the area and dig out the bodies + there is also the risk of a second wave. With still so much people missing it will be some time before they dig everyone out

