The Boston Police Relief Association memorial at Mt. Hope Cemetery was targeted in this week's vandalismBoston Police Relief Association, Facebook

Massachusetts police are investigating the separate instances of vandalism

Boston memorials honoring veterans and fallen police officers were vandalized in separate instances this week.

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CBS News reports that several memorials at the Mount Hope Cemetery in Mattapan and the WWII Memorial in Castle Island were doused with some type of oily liquid.

The Boston Police Department said that at Mount Hope Cemetery, The Boston Police Relief Association Memorial was vandalized, as well as Civil War, Spanish American War, WWI & WWII, Knights of Columbus and Free Masons memorials.

The Boston Police Relief Association said on Facebook on Tuesday that it condemns "in the strongest possible terms" the vandalism that occurred:

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The WWII Memorial near Castle Island, South Boston, which "commemorates the 216 soldiers from South Boston and Dorchester killed during World War II," was also vandalized separately.

Speaking about the WWII Memorial in Castle Island, U.S. Rep. Stephen Lynch told the American Military News on Monday: “It’s disgraceful. Absolutely disgraceful."

"These men gave their lives in fighting Nazi Germany.”

“It’s a sign of the times. The world has just gone crazy,” Lynch added.

On Facebook, the Thomas J. Fitzgerald VFW Post 561 in South Boston thanked those who were working to restore the WWII memorial :

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Boston’s Mayor Martin Walsh said: “These acts of vandalism will not be tolerated in our city.”

“Together with the Boston police, we will make sure anyone involved will be held responsible," Mayor Walsh added.

The Boston Police Department, who has launched an investigation into the matter, is asking the public to come forward with any tips about who may be responsible.

On Tuesday, Boston police officer James Kenneally said there had been no discovery of a connection between the Mattapan and Castle Island vandalism.