A video posted on Instagram shows taggers spray painting the walls of the notorious tunnel located between Figueroa and Hill Streets.
"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," the Instagram post by @gafftv reads.
Our ABC7 photojournalist went into the tunnel Monday night, getting a unique view of how the graffiti has grown.
Both sides of the tunnel are now covered with colorful graffiti from beginning to end.
Eyewitness News reached out to the mayor's office and the Bureau of Street Services for comment, but has not heard back.
This comes after taggers took over the towers at Oceanwide Plaza, also in downtown L.A.
More than a year later, the graffiti has still not been removed.