Trump's tweet was one of many from politicians voicing support

Shooting spree that killed 20 comes less than a week after Gilroy Garlic Festival

WASHINGTON – President Donald Trump called a mass shooting at an El Paso Walmart that left 20 victims dead and many more wounded "an act of cowardice" Saturday evening.

"Today’s shooting in El Paso, Texas was not only tragic, it was an act of cowardice," he tweeted. "I know that I stand with everyone in this Country to condemn today’s hateful act. There are no reasons or excuses that will ever justify killing innocent people."

In an earlier tweet Saturday, Trump pledged the "total support" of the federal government in the wake of the mass shooting.

Trump's tweet of support and sympathy were among many expressions of condolence and other emotions that federal officials shared Saturday in the hours following the massacre.

Texas Rep. Veronica Escobar abruptly ended a town hall. Beto O'Rourke choked back tears. House Speaker Nancy Pelosi – once again – called for an end to mass shootings.

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"Our hearts ache for the families of those who were killed & the injured," she tweeted. "Action must be taken to finally #EndGunViolence."

The shooting in El Paso follows a shooting Sunday at the annual Gilroy Garlic Festival in California that left three dead and more wounded.

House Speaker Nancy Pelosi proclaimed "enough is enough" while chiding Senate Republicans.

“Too many families in too many communities have been forced to endure the daily horror of gun violence. Enough is enough," she said in a statement. "The Republican Senate’s continued inaction dishonors our solemn duty to protect innocent men, women and children and end this epidemic once and for all."

In the past 10 years, America has entered a new and disturbing era of mass shootings. The number of incidents is increasing, according to FBI data, and they are becoming more deadly.

“The Justice Department joins in mourning with the people of El Paso, Texas," said Attorney General William Barr in a statement. "Those who commit such atrocities should be held accountable swiftly and to the fullest extent the law allows.”

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O'Rourke cut a campaign trip short to return to his home town of El Paso where the current Democratic presidential candidate served as its congressman until January.

"Lot of injury, a lot of suffering in El Paso right now," O'Rourke said, his voice breaking at times, during a hastily called news conference. "I'm incredibly saddened. It's very hard to think abut this. But I'll tell you, El Paso is the strongest place in the world. This community is going to come together."

Escobar, a freshman Democrat who represents El Paso, was roughly an hour into the town hall at the city's Coronado High School when she received news of the shooting.

"You all, I am so sorry, there's an active shooter. We are going to need to clear the event," said Escobar. After an aide immediately tells her something, Escobar quickly clarified the incident was near Cielo Vista Mall, roughly 14 miles away.

Later, she tweeted that she was "utterly heartbroken" over the incident.

Some of the other federal officials who weighed in include Vice President Mike Pence, who offered his prayers to victims and their families.

"Our hearts go out to the victims of this horrific shooting and to the entire community in this time of loss," GOP Texas Gov. Greg Abbott said in a statement. "While no words can provide the solace needed for those impacted by this event, I ask that all Texans join Cecilia and me in offering our prayers for the victims and their families."

Contributing; Elizabeth Weise, Sean Rossman, John Moritz