There are several posts and comments about the parts of the ISS striking Earth on re-entry. Here is one example
Would the ISS actually burn up completely? It's pretty big.
No, the Mir was much smaller and about 40 tons of debris ended up in the seas somewhere when it was decommissioned. Source
There are also a number of posts that talk about ISS re-entry, either planned or not, some examples:
- What is the likely plan to deorbit the ISS given its size and shape?
- For a given amount of fuel, what is the best de-orbit profile for the ISS?
- Why does the ISS have to be destroyed?
- What would happen to the ISS if we stopped maintaining it?
But I don't find anything that talks about what parts would survive, and what real danger those parts would pose.
Worst case scenario, with the current ISS configuration which parts would not burn up on re-entry and would survive to strike Earth. If one or more of those impacted a major city what would the likely outcome be?