The Venice City Council plans to increase the reward to track down the people responsible for defacing a veterans' memorial from $2,000 to $10,000.
A local former Marine who's featured in the mural spoke to 10News about his disappointment.
"I'm just shocked that someone can be so insensitive to do something like that and not have a conscience," said Stephen Lanier.
Lanier served 17 years in the Marines. He served in the first Gulf War.
He was stationed in Pico Rivera when a photographer and artist asked him to model for the mural alongside four other military members.
"That was an honor representing on that wall," said Lanier.
The original artist, no longer alive, painted the mural in 1992 and it's been untouched all these years.
Vandals had spray painted much of the lower half of the wall with a thick sheen of white and silver paint. The wall bears the names of 2,273 veterans who vanished in Vietnam.
"These are people who haven't been brought home. They haven't been buried properly," said Lanier. "That was their version of a tombstone. To disrespect a tombstone like that, what type of people are we dealing with?"
Word of the vandalized Vietnam memorial inspired so many veterans, some from Arizona, to clean up the spray painted mess. So far, police haven't made any arrests.
"Pretty sooner or later, they're going to slip up and they're going to get caught," said Lanier.
By Memorial Day, volunteers had taken off much of the graffiti. But since there was no protective coating, many of the names came off, too.
Vandals didn't tag the faces of Lanier and the other military members.
There is a list of the original names, and volunteers said they'll repaint all the names.