#Vandal dumps red paint on ‘Black Lives Matter’ mural outside Trump Tower

Mayor Bill de Blasio’s giant Black Lives Matter mural outside Trump Tower is already getting dumped on.

An unidentified man walked up to the giant mural outside the Midtown skyscraper and poured red paint on the bright yellow letters shortly after noon Monday, then ran off before cops showed up to survey the damage.

“I knew it was going to happen — there’s all this racist s–t going on,” construction worker Billy McCabe told The Post. “The mural shouldn’t have been done right in front of Trump Tower.”

The mural, announced by de Blasio earlier this month, has already become a flashpoint for face-offs between pro- and anti-Trump forces — including an ugly back-and-forth on Saturday.

De Blasio commissioned the mural last month, and on Thursday he was jeered by protesters as he helped paint the mural with First Lady Chirlane McCray and the Rev. Al Sharpton.

Police said the assailant who vandalized the massive message Monday walked up Fifth Avenue at 12:13 p.m. wearing a black shirt and a black hat, dumped the paint then ran down 56th Street, police said.

The blotch of paint, dumped between “Black” and “Lives,” was then smeared over much of the mural by passing traffic.

“I wish I’d tackled him, but I’m old and fat so I didn’t,” said Paul Rossen, who wore a “Dump Trump” face mask, a BLM tee-shirt and was selling anti-Trump merchandise nearby when the vandal showed up.

“I don’t like anybody blocking free speech, and even though I hate Trump I would never think of vandalizing something pro-Trump,” he said.

Nearby, a man with a MAGA hat walked back and forth holding a sign that read, “The only time black lives matter is when they are shot by a white policeman or an Oreo cookie. Defend all policemen.”

“He shouldn’t have done it, but that shouldn’t have been there in the first place,” the man, who gave his name as Michael, said of the vandal and defaced mural.

Additional reporting by Craig McCarthy