The mother of an Arizona officer killed by an illegal immigrant was on “The O’Reilly Factor” tonight.

Back in May, police officer Brandon Mendoza was off-duty and driving on a freeway when he was hit head-on and killed by a drunken driver, who also died in the crash. The driver, Raul Silva-Corona, was an illegal immigrant.

In 1994, Silva-Corona was charged with assaulting a police officer and burglary in Colorado, but did not show up for his hearing. In 2002, he was apprehended by Border Patrol and sent back to Colorado, where he was sentenced to three years of probation.

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Mary Ann Mendoza penned a letter to President Barack Obama three weeks ago about the death of her son.

“I just ask him for an explanation of why illegal criminals are allowed to stay in our country and kill our citizens,” Mendoza said, contending that the president is soft on deporting criminals.

Mendoza has not yet heard back from Obama, but she hopes he will at least acknowledge that he received the letter.

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"My son took an oath to protect people in his community and he fought to get people like [Silva-Corona] off the street, to keep our community safe, and President Obama needs to acknowledge that there are problems like this happening, and our children are being killed by illegal criminals who are allowed to stay in this country and repeatedly commit crimes."

O'Reilly said he does not expect that Mendoza will receive an answer from the administration because "there is no answer," blasting the federal government for being "derelict" on this issue.

“You and I would be spending time for those crimes that he committed,” she said.

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Watch more above.