Armory -> Utes -> "Kill house" challenge

Hi.

I have problem with this challenge, because i cant find/see some hostile targets (terrorist - red ones).

Beginnng is easy. I reach the fountain, then turn left behind house, reach the gate of the farm (or something) and now i hear some target appears (this specific voice "pong") but i don't see where. I suppose that it appear in house i've just passed (usually i fail challenge here).

Another situation is in red building near the end. First of all two targets appears in windows, then (randomly) one in house, and after couple of steps inside i hear some "pong" but i don't see nothing (and usually fail challenge).

I've never finished this challenege. Any remarks?

There's already at least one previous thread where this was discussed. I suggest you search the forum and read it.

EDIT: Ok, had it bookmarked and found it quickly: http://forums.bistudio.com/showthread.php?t=94889