They cannot force you or go after your property. However they can try to recover from the estate of the deceased i.e. your father’s property. For this they’ll have to approach the courts and file a money/recovery suit.
There is a legal doctrine called “pious obligation” which means the legal heir is morally bound to repay his/her father’s/mother’s debt. Again for this they’ll need to approach the courts and file a suit against you.
They might not approach the courts practically owing to the costs involved, doesn’t mean ideally they can’t or won’t.