If they were randomly shooting them into Israel, we can deduce their intent to hit civilians. If they were aiming them specifically at Israeli military targets, then we can deduce their intent to hit military targets. And yes, some people do take credit for killing children (as well as adult non-combatants). Although some people might prefer to say that no one is taking responsibility. Either way, no one has admitted to firing that rocket.

For my own part, it's not possible for me to know who did it or what they were targeting. I can only say under what circumstances I would condemn the act.