Dennis Marx, 48, was well-known to police and was due in the Forsyth County Courthouse Friday on weapons and drug charges, police said. But instead, he rammed his explosives-laden SUV onto the courthouse steps around 10 a.m., tossing tire-penetrating "stop sticks" and a smoke bomb out the window to slow down pursuing vehicles before engaging Forsyth County Deputy Daniel Rush, a 25-year veteran, in a fierce gun battle.