I do have to wonder if only Reapers can fight back, or if it would be possible to defend oneself against them. It stands to reason, if they can be killed.

[Is he talking to the group, or just himself?]

But yes, I have no doubt that the number of murders will only increase. Now that they believe there are only a limited amount of people who will get to return to life, they're sure to turn on one another in the hopes that the rest of us will focus on the Reapers.