Leading Native American advocacy groups are denouncing President Trump Donald John TrumpHR McMaster says president's policy to withdraw troops from Afghanistan is 'unwise' Cast of 'Parks and Rec' reunite for virtual town hall to address Wisconsin voters Biden says Trump should step down over coronavirus response MORE for citing Wounded Knee Massacre and the Battle of Little Bighorn in derogatory comments made against Sen. Elizabeth Warren Elizabeth WarrenWarren, Schumer introduce plan for next president to cancel ,000 in student debt The Hill's 12:30 Report - Presented by Facebook - Don't expect a government check anytime soon No new taxes for the ultra rich — fix bad tax policy instead MORE (D-Mass.).

“We condemn in the strongest possible terms the casual and callous use of these events as part of a political attack," Jefferson Keel, president of the National Congress of American Indians, said in a statement on Monday.

"Hundreds of Lakota, Cheyenne, and Arapaho people lost their lives at the hands of the invading U.S. Army during these events, and their memories should not be desecrated as a rhetorical punch line."

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The comments came after Trump on Sunday mocked Warren for an Instagram Live video she posted shortly after she announced her 2020 White House bid against him.

"If Elizabeth Warren, often referred to by me as Pocahontas, did this commercial from Bighorn or Wounded Knee instead of her kitchen, with her husband dressed in full Indian garb, it would have been a smash!" Trump tweeted, referring a video Warren casually drinks a beer and introduces her husband.

The Battle of Little Bighorn, which occurred in 1876, was a clash between U.S. cavalry units and Native American tribes that resulted in hundreds of deaths on both sides. The Wounded Knee Massacre of 1890 was an event where U.S. troops slaughtered hundreds of men, women and children of Lakota Sioux.

The massacre has been viewed as a symbol of the brutality experienced by Native Americans under European-Americans.

Rodney Bordeaux, Chairman of the Rosebud Sioux Tribe and NCAI Great Plains Alternate Area Vice President, also condemned Trump for using "one of the darkest and most tragic chapters in the history of the Sioux Nation" to attack Warren.

Standing Rock Sioux said on Twitter on Monday that it had reported Trump's tweet as "abusive and harmful."

We reported this as abusive and harmful because it is; you should too! https://t.co/bVhTAcXspF — Standing Rock Sioux (@StandingRockST) January 14, 2019

Multiple Republican senators also called on Trump to avoid referencing the Wounded Knee Massacre as a tool to attack his political opponents.

"I wish he wouldn’t tweet as much, [as] I’ve said many times in the past. That’s obviously a very sensitive part of our state’s history. So yeah, I wish he’d stay away from it," Sen. John Thune (S.D.), the No. 2 Senate Republican, told reporters.

Sen. Mike Rounds (R-S.D.) added on Twitter that the Wounded Knee Massacre was one of the "darkest" moments in U.S. history, saying that "it should never be used as a punchline."