There is no “extremely” in the word critical. Ever.
Critical is the polar opposite of “stable”, so it is absolutely impossible to be both.
So. This means we know nothing about the officer’s condition, in this ignorant title, due to this illiterate writer.
Actually one can be critical but fairly stable Someone with pneumonia on a ventilator is certainly critical but can be relatively stable and expected to improve. Someone else who has already had 2 cardiac arrests in the last hour and is hanging on by a thread is also critical - but in a whole different situation