When asked whether online writings believed to be written by the suspected shooter that El Paso police have said they were using as a "nexus to a potential hate crime" could also be linked to Trump's rhetoric against immigrants and racist postings toward four minority congresswomen, O'Rourke paused briefly before answering, "Yes."

"We've had a rise in hate crimes every single one of the last three years during an administration where you've had a president who's called Mexicans 'rapists' and 'criminals,' though Mexican immigrants commit crimes at a far lower rate than those born here in the country," O'Rourke said while speaking to the media after meeting with victims and medical staff at University Medical Center in El Paso. "He is a racist and he stokes racism in this country, and it does not offend our sensibilities, it fundamentally changes the character of this country and it leads to violence."

Trump called the mass shooting an "act of cowardice," and said there "are no reasons or excuses that will ever justify killing innocent people."

He ended his two-tweet message by saying he and first lady Melania Trump sent "heartfelt thoughts and prayers to the great people of Texas."

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