Russia firing artillery on Ukraine troops: US

[HooptieWagon]

41. Update:

Since the US spokesperson didn't specify the type of artillery, I selected a typical medium sized, long range, Soviet made gun-howitzer that appears to be still widely used.
http://en.m.wikipedia.org/wiki/152_mm_towed_gun-howitzer_M1955_(D-20)
Maximum range is 15 miles using a rocket-propelled projectile (which likely isn't being used in this case). Effective range is 11 miles. Either probably requires a forward observer to direct fire. W/O a forward observer, they'd either be dropping random shells to harass, or firing close range (within line of sight) where targeting can be done from near the gun position.
This gun is towed behind a heavy truck, and requires a dozen or more men to operate. Very possible the same system is mounted on heavy, self-propelled, tracked vehicles.