Tijuana (CNN) A group of deported US veterans gathered Saturday at Friendship Park in Tijuana, Mexico, before Memorial Day to repaint a mural of an upside-down American flag. The mural, faded and covered in graffiti since it first went up in 2013, is the centerpiece of the park, which sits at the edge of the US-Mexico border, where a border wall juts out into the Pacific.

An upside-down flag is a sign of distress, and the crosses in place of stars are symbols of those who die trying to cross the border, said Amos Gregory, the mural's artist and a Navy veteran who works with the deported vets. A lot of people don't realize US veterans, if they are not citizens, can get deported.

"We're touching it up," Gregory said of the mural. "We try to do it at least yearly, to get down here together."

They planned to repaint it last month, but that was put on hold after the US Border Patrol indicated it was considering whether to remove or alter Gregory's mural. Though on the Mexican side of the wall, it's on US property, one of multiple layers of fences the United States has up around the area, and Border Patrol received a complaint

"We're back here doing this regularly scheduled painting, but we have this backdrop now," Gregory said. He said he thinks they're in the clear after Border Patrol didn't do anything following a 48-hour window in which the mural was supposed to be gone.

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