How is rebel violence against civilians linked to the overall fighting in internal conflicts? This paper approaches the question by arguing that the way rebels respond to fighting depends on their military capabilities relative to the government. The dynamics of violence tend to be different depending on whether parties approach parity or if there is a strong asymmetry: whereas strong groups, usually operating in militarily weak states, can use more offensive tactics, weak groups challenging a strong state have to rely much on guerrilla tactics. It is proposed that weak groups target civilians to compensate for lacking resources, and therefore the magnitude of violence against civilians increases as fighting intensifies. Strong groups, on the other hand, produce a different dynamic where civilians are often targeted with the intention of gaining territorial control, and such violence is consequently unrelated to the intensity of fighting. Using detailed data on the number of civilians killed by each rebel actor in all internal conflicts from 1992 to 2004, the argument is evaluated statistically and by a careful examination of the data. The empirics clearly show that violence by weak groups indeed is closely correlated with the intensity of fighting, whereas there is no correlation to be found for strong groups. It is concluded that by looking deeper into the interplay between various forms of violence and the complexities of relative military capabilities, we can further our understanding of contemporary warfare.