A memorial dedicated to Vietnam War veterans was partially covered with graffiti tags last week in the Venice area of Los Angeles, the L.A. Times reports.

Local authorities say they are hoping to clean the memorial soon, and police say they will be patrolling the area around the memorial, which has been present in the community since Vietnam veteran Peter Stewart painted it in 1992.

The vandalism has sparked outrage when it was first noticed on May 25.

“It’s a desecration of something that’s a tribute to people who went off to war, in a very unpopular war, and they never came back,” George Francisco, vice president of the Venice Chamber of Commerce, told local affiliate ABC-7. “The children who tagged this are ignorant. The children who tagged this don’t even know that it’s Memorial Day.”

Stewart Oscars, a Venice resident and the man who first reported the vandalism, told the L.A. Times he felt instantly nauseous when he saw it.

“This knocked me out. So sickening. Just sadness…think of all these people. They’re gone,” he told CBS L.A. “I remember the Vietnam war and how friends went to war, and bodies came back.”

Francisco said the chamber is working to repair the wall as soon as possible, and an official of the Los Angeles Metro, which owns the wall, said the police department would be monitoring the area closely.

Westside City Councilman Mike Bonin called it a “disgusting and disgraceful act.”

He said his office was working with the Board of Public Works and L.A.’s Office of Community Beautification to have the mural cleaned as soon as possible.

The desecration of the L.A. site is far from unique, however, as other memorials were damaged within a few days of Memorial Day. A man drove through a memorial cross display in Kentucky, and the Petersburg National Battlefield in Virginia was reportedly looted.