WASHINGTON (AP) — Workers continued cleaning residue from green paint that was splattered on the Lincoln Memorial in an apparent case of vandalism, and a union representing officers who guard the National Mall said it shows they need more resources.

Cleaners returned to the memorial Saturday to scrub away the paint while it was open to visitors. A National Park Service spokeswoman said they were working cautiously to prevent any damage.

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Over the weekend, the union representing park police officers said the vandalism shows the department needs more officers to protect monuments on the National Mall.

“This incident further underscores the need for the National Park Service to provide more funding and more personnel so as to provide a higher level of deterrence through officer presence,” U.S. Park Police Union President Ian Glick said in a statement. “We are fortunate that this deplorable act can be remedied but caution that we are lucky that this wasn’t an act of terrorism.”

Meanwhile, a Virginia woman said she discovered the vandalism and reported it to U.S. Park Police about 1:30 a.m. Friday. Jamie McDaniel of Stafford, Va., said she was showing a friend the memorial and went there late to avoid the crowds. About 20 people were visiting the memorial at that hour, she said.

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McDaniel said she was stunned to see green and white paint splattered on the Lincoln statue. She then found two Mountain Dew bottles nearby that were overflowing with paint.

McDaniel said she found a U.S. Park Police officer within about five minutes. The officer didn’t question her or ask her name, though, which surprised McDaniel, she said.

U.S. Park Police officials said they were not aware McDaniel had reported the vandalism, and they would like to speak with her.

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