electromagnetism - Why are six real numbers, $vec E$ and $vec B$, needed to paramaterize the electromagnetic force, even though force needs only three?

Since force is a vector, three components are enough to define it completely at some point in space and instant of time. Yet the electromagnetic force requires two independent forces, the electric and magnetic, and therefore six components to fully define it.

What is it about the electromagnetic force that requires six components to completely define it, rather than just three for force generally?