2020 candidates Julian Castro, Beto O'Rourke, both from Texas, slam President Trump over mass shootings

The two 2020 candidates also called for stricter gun control legislation.

Former Housing and Urban Development Secretary Julián Castro said "it’s so unfortunate that not only our president, but his administration can’t rise up to the challenge of leadership in these times.”

Castro was responding directly to a prior interview on "This Week" with acting White House chief of staff Mick Mulvaney.

"The president is just as angry by this as you are, and wants to do something about it just as much as everybody else does," Mulvaney said. "This was a sick person. The person in Dayton was a sick person. No politician is to blame for that."

Castro responded by still placing the blame with the president's rhetoric.

“Anybody who has the ability to see and hear and understand what the president has been doing since he started his campaign in 2015 knows that division and bigotry and fanning the flames of hate has been his political strategy," he said. "That's how he believes that he won in 2016.”

In a separate interview with ABC News Chief White House Correspondent Jonathan Karl on “This Week," Beto O'Rourke, the former congressman who represented El Paso, accused Trump of encouraging racism through his inflammatory rhetoric. When asked about his previous statements that Trump is fueling hate and if he thinks the president bears responsibility for the mass shooting in El Paso, O'Rourke said "I am because he does. Someone who describes Mexican immigrants as rapists and criminals, who has sought to ban all -- all Muslims, all people of one religion -- from traveling to the United States or who calls Nazis and white supremacists very fine people -- he doesn't just tolerate, he encourages the kind of open racism and the violence that necessarily follows that we saw here."

O’Rourke left the campaign trail to return to his hometown on Saturday night. He toured one of the hospitals that had taken in victims of the shooting. On "This Week" he described having seen a woman who was shot in the chest, as well as her mother and aunt who were also victims of the shooting.

“It’s incredibly heartbreaking to see what these families are going through right now,” he said.

Twenty people were killed and 26 people were injured in a mass shooting Saturday at an El Paso, Texas, Walmart, officials said.

Another mass shooting occurred in Dayton, Ohio, just over 12 hours later. Police have said that nine people are dead and more than a dozen are wounded.

Authorities in El Paso identified the suspect as Patrick Crusius, 21, of Allen, Texas. An assault style riffle, similar to an AK-47, was found at the scene of that mass shooting, officials said.

El Paso police Chief Greg Allen said authorities are examining a "manifesto," they believe was written by the shooter and shows a possible "nexus" to a hate crime.

Cielo Vista Mall, where the Walmart is located, is one of El Paso's most popular malls, especially among Mexican tourists who come to the U.S. to shop. At least three Mexican nationals were killed in the attack, Mexican President Andres Manuel Lopez Obrador said.

Castro said “the evidence points to the idea that it was a hate crime,” on “This Week” Sunday.

“[The shooter] traveled from Allen, Texas, more than nine hours away to go specifically there,” he added. “There was a very Hispanic-heavy area. So it certainly looks like a hate crime. And now the important thing is what are we going to do about it?”

O’Rourke called for “sensible gun policies” and added that “we also need to connect the dots on this hatred and racism that is coming from the highest positions of power in this country."

Castro brought up Texas's concealed carry laws and noted that the threat of other armed individuals did not discourage the attack.

“This happened in Texas, where we have concealed carry, we have open carry, we have campus carry, we have one of the highest rates of gun ownership," he said. "That shooter knew that he was walking into a situation where a lot of folks there could be carrying a weapon. That didn't stop him. The answer is not more guns. The answer is to make sure that these weapons of war, these semiautomatic weapons, don't get into the hands of people who go and use them on the street."