SAN ANTONIO — San Antonio presidential candidate Julián Castro unleashed a new ad in which he blames President Donald Trump for having a role in the El Paso massacre.

"As we saw in El Paso, Americans were killed because you stoked the fire of racists," Castro said. "Innocent people were shot down because they look different from you. Because they look like me. They look like my family. Words have consequences. ¡Ya Basta!"

The Trump 2020 campaign sent a statement to KENS 5 Tuesday. Communications Director Tim Murtaugh said:

"Castro's campaign has failed and he's the only one who doesn't know it yet. Does he think he bears any responsibility for the lunatic who shot at an ICE office in his hometown of San Antonio this morning? Using his own logic, he should ask himself that question."

Murtaugh is talking about officials from the FBI and Homeland Security joining in the investigation efforts into a shooting at two federal offices overnight Tuesday in San Antonio.

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However, Castro is making sure the president himself sees the ad. According to reports, his campaign spent nearly $3,000 to run the ad in Bedminster, New Jersey on Wednesday. It is the place where President Trump is expected to be this week.

Dr. Robert Marbut has worked on both sides of the aisle. KENS 5 showed him the ad to analyze. "This is probably the best $3,000,or $4,000 buy any candidate has made in probably 20 years," he said. "It is an aggressive ad, and I think that is what he needs now."

Dr. Marbut, who teaches political science at Northwest Vista College, said Castro is playing up two major issues: immigration and gun control. He said it is bold for Castro to point the finger at the president and connect him to the mass murder in El Paso.

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"If you take the shooter's manifesto that he released and Donald Trump's speeches and start lining them up, you see phrase, word, phrase, word in the same sequence and same order," Marbut said. "The parallel is shocking that it would be hard for the president to come back and say, 'no I didn't.' I mean, it really is tied to him."

Marbut said this ad will help Castro get to the next presidential debate coming up next month in Houston.

The Castro brothers have been feuding with Trump for a week now. Julian's brother, Congressman Joaquin Castro, tweeted a list of San Antonians he said donated to the Trump campaign.

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