EL PASO, Texas (CBSDFW.COM/AP) – The government has filed hate crime charges against, Patrick Crusius, the man who admitted targeting Mexicans and shot to death 22 people at a Walmart store in El Paso in August.

Word of the changes comes from a person familiar with the matter who spoke to The Associated Press. That source says a multicount federal indictment against suspected gunman Crusius of Allen is expected to be announced later Thursday at a news conference in El Paso.

The 21-year-old attended Liberty High School in Frisco but later transferred to Plano Senior High School, where he graduated in 2017. He also attended Collin College from fall 2017 to spring 2019.

At the time of the shooting, El Paso Mayor Dee Margo said police investigated whether a document posted online shortly before the shooting was written by Crusius. In it, the writer expresses concern that an influx of Hispanics into the United States will replace aging white voters, potentially turning Texas blue in upcoming elections and swinging the White House to the Democrats.

The writer was also critical of Republicans for what he described as close ties to corporations and degradation of the environment. Though a Twitter account that appears to belong to Crusius included pro-Trump posts praising the plan to build more border wall, the writer of the online document says his views on race predated Trump’s campaign and that any attempt to blame the president for his actions was “fake news.”

Denying he was a white supremacist, the writer said “race mixing” is destroying the nation and recommends dividing the U.S. into territorial enclaves determined by race. The first sentence of the four-page document expressed support for the man accused of killing 51 people at two New Zealand mosques in March after posting his own screed with a conspiracy theory about non-white migrants replacing whites.

The person who spoke to AP had direct knowledge of the case but was not authorized to disclose details of the indictment before the public announcement.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)