A graffiti vandal in Midtown was caught red-handed on Tuesday, cops said.

The tagger was posting “fuel” in red spray-paint on public property when undercover detectives spotted him on 45th Street and 5th Avenue around 11:30 a.m., cops and witnesses said.

He was tackled to the ground and hauled to the station house where he has yet to be charged, police sources said.

Cops said this is not his first offense.