LOS ANGELES -- (CBS NEWS) Memorials to veterans in a Los Angeles neighborhood and a town in Kentucky, as well as a Civil War veterans cemetery in Virginia, were damaged as the nation prepares to mark Memorial Day, officials said.

A Vietnam War memorial in the Venice area of Los Angeles was extensively defaced by graffiti, CBS Los Angeles station KCBS reported.

The mural, painted on a block-long wall on Pacific Avenue, lists the names of American service members missing in action or otherwise unaccounted for in Southeast Asia.

The wall for missing veterans has been tagged previously, but the latest vandalism covers the bottom half of the memorial for much of its length.

To George Francisco, vice president of the Venice Chamber of Commerce, it's not just graffiti. "It's a desecration. I mean it's very simple. There's no sort of other way around it," Francisco, who also runs a nonprofit called Veterans Foundation Inc., told KCBS.

"I've known the sacrifices these people made in an incredibly unpopular war. So to continue the mistreatment of Vietnam veterans is somewhat shocking, somewhat shocking and quite sad," Francisco said.

Painted by a Vietnam veteran and dedicated in 1992, it declares, "You are not forgotten" and states the number of missing as 2,273.

"This knocked me out. So sickening. Just sadness... Think of all these people. They're gone," Venice resident Stewart Oscars told the station. "I remember the Vietnam War and how friends went to war, and bodies came back. Somehow, it has to be taught that this is not a good idea. This is actually stupid."

According to the Defense POW/MIA Accounting Agency, the number of unaccounted-for Americans was listed at 2,646 in 1973. About half were those missing in action, and the others were those killed in action but the body was not recovered.

Since then, the remains of more than 1,000 American have been identified and returned and about 1,600 have still not been accounted for, although efforts continue.

The Los Angeles Police Department said it was not investigating the case.

News of the vandalism came as another veterans-related memorial was reported damaged in Henderson, Kentucky. Police say a Memorial Day cross display there that honors the names of 5,000 veterans of conflicts dating back to the Revolutionary War has been vandalized by a driver who plowed through the crosses early Saturday.

Jennifer Richmond, a spokesman for the Henderson Police Department, said the community was devastated and working frantically to repair and replace the crosses that were put on display for a Memorial Day ceremony in Central Park.

She said a 27-year-old local man drove straight through the cross display in the Henderson park, about 130 miles west of Louisville, just before 6 a.m. Saturday, but investigators don't know if it was deliberate.

CBS affiliate WKLY reported Anthony Burrus was charged with criminal mischief in the first degree and leaving the scene of an accident. Online jail records do not list an attorney for Burrus.

In Virginia, the Petersburg National Battlefield has apparently has been looted, the National Park Service said. Numerous excavations were found at the Civil War battlefield last week, Jeffrey Olson, and agency spokesman, said in a news release Friday.

Petersburg National Battlefield is a 2,700-acre park marks where more than 1,000 Union and Confederate soldiers died fighting during the Siege of Petersburg 151 years ago.

"Unfortunately, it's most likely for profit. There is a market out there," Chris Bryce, chief of interpretation at the battlefield, told CBS affiliate WTVR.

Stealing artifacts from the battlefield violates federal law. Violators could face two years in prison, WTVR reported.

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