In downtown Los Angeles, the 2nd Street Tunnel has once again been overtaken by graffiti—just hours after crews painted over its walls in a major cleanup effort.The tunnel, which runs between Figueroa and Hill Streets, was given a fresh coat of paint at noon. By midnight, vandals had already returned, covering the walls from end to end.A video posted on Instagram shows taggers spray painting the tunnel’s interior, with the post from @gafftv describing the scene: “What had been a clean slate at noon became by midnight a living gallery of street expression, filled with burners, rollers, and painted signatures from L.A.’s most well known vandals.”ABC7 crews captured video late Monday night showing how quickly the tunnel was covered again with colorful tags. The city has not yet commented on the situation, despite Eyewitness News reaching out to the mayor’s office and the Bureau of Street Services.This latest incident follows a wave of graffiti that has plagued downtown Los Angeles,…..