PHILADELPHIA (CBS) — Police are investigating vandalism in a local neighborhood that threatens President Donald Trump.

The Homeland Security Unit of the Philadelphia Police Department began investigating graffiti vandalism in Manayunk on Monday and says the Secret Service may get involved.

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This comes after neighbors reported finding the words “Kill Trump” spray-painted across a wall on the 100 block of Mallory Street.

“Of course we take that kind of thing seriously any time a public figure is directly threatened that way,” said Philadelphia Police Capt. Sekou Kinebrew. “You presume the highest, that it is a credible threat until proven otherwise.”

“In my opinion, you shouldn’t be writing ‘Kill Trump,'” said neighbor Hayden Carroll. “I don’t support Trump, I don’t agree with him, but he is our president so I do find it a little offensive.”

Just yards away, neighbors reported seeing more graffiti: a symbol used to represent anarchy spray-painted twice on a garage.

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Another neighbor, Jim Roynan, says graffiti vandalism is popping up more frequently in the neighborhood and while he doesn’t support the violent message against the president, he supports the right to write it.

“It’s America. You have both sides and that’s how it goes,” he said.

As an artist, he hopes the city will give him permission to paint a mural over the graffiti.

“I’m an artist myself. I’m not saying that’s art but it’s someone’s expression and how they feel,” he said.

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Neighbors say they have also notified 311 and expect the graffiti to be removed soon.