The Southern Poverty Law Center (SPLC) dropped a bombshell on Tuesday, announcing it had over 900 emails that White House aide Stephen Miller sent to former Breitbart writer and editor Katie McHugh.

According to the SPLC, in the emails, Miller aggressively "promoted white nationalist literature, pushed racist immigration stories and obsessed over the loss of Confederate symbols after Dylann Roof's murderous rampage."

Over 80% of the emails contained some reference to race or immigration.

The revelation is deeply disturbing given Miller's senior role in the Trump Administration. Miller is seen as the architect of Trump's child separation policy, Muslim bans, and the decision to refuse Bhamaian refugees after a devastating hurricane.

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In the emails, Miller presses McHugh to write about "The Camp of the Saints," a racist French novel by Jean Raspail popular among white nationalists. The book fictionalizes themes of "white genocide" and "great replacement" conspiracies popular among the alt-right.

McHugh was fired by Bretbart in 2017 for making Islamophobic tweets.

Miller also sent her stories from the white nationalist website VDARE and anti-immigrant stories taken directly from the American Renaissance, a white-supremacist publication.

The emails reveal Miller as a man obsessed with non-white crime statistics.

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"When discussing crime, which he does scores of times, Miller focuses on offenses committed by nonwhites," the SPLC reports. "On immigration, he touches solely on the perspective of severely limiting or ending nonwhite immigration to the United States."

"Americans should be terrified by the casual way that Stephen Miller, who has enormous influence in the White House, shares racist content and speaks the language of white nationalists in emails to people he apparently considered fellow travelers," Michael Edison Hayden,the author of the report, said in a statement.

As a response to the disturbing email leak, Representative Alexandria Ocasio-Cortez of New York has called for Miller's resignation.

"Stephen Miller, Trump's architect of mass human rights abuses at the border (including child separation & detention camps w/ child fatalities) has been exposed as a bonafide white nationalist," Ocasio-Cortez tweeted on Tuesday afternoon. "He's still at the White House shaping US immigration policy. Miller must resign. Now."

The emails sent by Miller came during the presidential election from March 4, 2015, to June 27, 2016 when he was working for then-Senator Republican Jeff Sessions.

The Trump Administration has refused to discuss the Miller emails; instead, focusing on the SPLC. In statement to The Huffington Post, White House press secretary Stephanie Grisham said the SPLC was "utterly-discredited, long-debunked far-left smear organization."