CNN reported that an "observation platform" was overrun. The base itsself wasn't. Someone who knows what they're talking about can comment further, but it sounds to me like someone may have made a fatal mistake. Sounds like the platform was set up so that the bad guys could generate an intense volume of fire on it from civilian buildings, but the good guys couldn't return fire en masse because of the civilians.

Details are still sketchy, but if the deceased were more worried about being amongst the population than ensuring they always had a firepower advantage, then B is very relevant. (Assuming my assumptions are correct of course, which they may not be.)