Housing and Urban Development Secretary Ben Carson said Monday that Rep. Maxine Waters (D-CA) lacked “basic manners” in penning a letter to President Donald Trump last month saying his “shamelessness knows no bounds.”

Waters’ October 28 letter demanded answers from the Trump administration about its plan to push homeless Californians out of homeless encampments, Politico reported.

The Washington Post reported in September that the administration has pushed for a crackdown on homeless encampments in California, with aides discussing the possibility of moving them to government-run facilities.

“Shamelessness,” Carson wrote in a reply letter obtained by Politico, “is a career politician of 30 years laying blame. Shamelessness is allowing more than 55,000 Americans to live on the very streets they represent,” referencing Waters’ district in southern Los Angeles County.

Carson added that he wrote multiple letters to Waters’ office with the intent of meeting to discuss the homelessness crisis in her district but claimed she had refused to meet him.

“Basic manners elude you and it seems that instead of producing results, you’re more interested in producing cheap headlines at the President’s expense — like a true career politician,” Carson continued.

In response to Carson’s letter, Waters told the Hill that Carson is incompetent and “a complete failure at HUD.”

“All of this demonstrates his lack of competence as HUD secretary and the cruelty of this Administration. Instead of whining about his inability to get on my schedule, he should take some time to focus on the over half a million people experiencing homelessness in this country,” Waters said.