>>> The following sentence appears on a local newspaper in Hong Kong
>>> today.
[quoted text clipped - 11 lines]
>> "police warned that there would be reprisals." This use of
>> OF is common in English.
More simply, "of" is often a synonym of "about". That's not quite what
it is here, but probably close enough to show what the sentence is
doing.
> If "reprisals" is any sort of object, I'd argue that it's a *direct*
> object.[1] An indirect object would be "them" immediately following
> "warned."
Or even the other way about, as Don implies. I don't think reprisals can
usefully be warned of anything.
> [1] Structurally, it's the object of a preposition, or course.

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Mike.