The largest police union in the U.S. demanded that Amazon remove a shirt from a third-party vendor that supports the Black Lives Matter movement.

The Fraternal Order of Police wants the online retailer to follow Walmart and remove a shirt that sports the words “Bulletproof: Black Lives Matter” across the chest, The Guardian reported Friday. Walmart removed the shirt from its store after the union called it “offensive.”

FOP President Chuck Canterbury wrote in a letter to Amazon CEO Jeff Bezos to support the union in “increasing the bonds of trust between the men and women of law enforcement and the communities they serve.”

As of Monday morning, the shirt was listed on the Amazon website, but was “currently unavailable.”

Canterbury told The Guardian that he wasn’t surprised that Amazon wouldn’t remove the listing and called the website a “pretty liberal marketer.”

WALMART STOPS SELLING ‘BULLETPROOF: BLACK LIVES MATTER SHIRTS ON ITS WEBSITE

He added that the issue was still important because of the “amount of violence demonstrated at Black Lives Matter marches and the fact that eight police officers had been assassinated while protecting Black Lives Matter protests,” – referring to the police killings in Dallas and Baton Rouge over the summer.

Canterbury sent a letter Tuesday to Walmart CEO Douglas McMillon, asking the company to remove the “offensive” shirts from the store.

“I urge you to prohibit the use of the use of the Walmart name and website for the retail sale of these products,” the letter read.

Time reported that the shirts were being sold through Walmart’s website by Old Glory Merchandise.

“Like other online retailers, we have a marketplace with millions of items offered by third parties that includes Blue Lives Matter, Black Lives Matter and All Lives Matter merchandise. After hearing concerns from customers, we are removing the specific item with the ‘bulletproof’ reference,” Walmart said in a statement.

Canterbury told The Guardian that the union would continue to pressure retailers who sell the Black Lives Matter merchandise until the group makes it clear that don’t approve of anti-police violence.

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