Complex sentence: It could also include boxes or piles of rubble that one wouldn't generally suspect, snipers have been getting more and more innovative in their attempts to conceal themselves so places that one wouldn't usually expect to hold a sniper can become suspect.
Split into simpler sentences: It could also include boxes or piles of rubble that one wouldn't generally suspect. Snipers have been getting more and more innovative in their attempts to conceal themselves so places that one wouldn't usually expect to hold a sniper can become suspect.