A desecrated American flag was left crumbled on the ground outside the NYPD Police Academy in Queens and the building was vandalized with red paint early Saturday morning, photos obtained by The Post show.

The thugs splattered paint on the sidewalks, the walls of the $950 million training facility on College Point Boulevard, and the poles out front. A rope line was also left hanging from the front of the building — as if someone had rappelled down from above, the photos show. 

The 730,000-square-foot complex, which opened in 2014, is monitored by 24-hour security — just steps away from where the attack occurred.

“What a security breach,” a police source told The Post.

“Everyone who has that security detail should be transferred immediately. They have one job. One job. What an embarrassment. There’s nothing else around that place.”

The red paint was splattered onto areas that are accessible to the public around 4 a.m., NYPD spokesman Edwin Sanchez said.

Police were “working on getting video” of the incident, and had no descriptions of the vandals, Sanchez added. 

Police sources told The Post they were having trouble accessing the cameras at the facility due to recent tech upgrades. They were trying to pull video from nearby cameras, the source said.

The American flag appeared to be ripped down from a pole outside the facility, police sources said, although the NYPD spokesman was unable to confirm that.

“That’s something that should never happen,” a retired detective, who spent more than two decades on the force said of the vandalism. “That building has many things in it that should be guarded 24/7.”