The father of a Muslim Army captain who died in Iraq challenged Donald Trump at the Democratic convention Thursday.

Captain Humayun S.M. Khan of Virginia died in 2004 after a vehicle packed with IEDs exploded near him, and he was buried in Arlington National Cemetery.

Standing on the stage in Philadelphia, his father, Khizr M. Khan, noted Trump’s call to ban Muslims from entering the U.S., held up a pocket copy of the Constitution and challenged the Republican nominee.

“Let me ask you: Have you even read the U.S. Constitution? I will gladly lend you my copy. In this document, look for the words liberty and equal protection of law,” he said, as the crowd broke into chants of “USA! USA!”

Khan also criticized Trump’s comments on immigration and his proposal to build a wall on the Mexican border.

With his wife at his side, Khan pleaded with the audience to honor the sacrifice of his son by voting for Clinton in November.

“My son had dreams too, of being a military lawyer. But he put those dreams aside when he sacrificed his life to save the lives of his fellow soldiers,” he said. “I ask all Muslim immigrants, all immigrants and patriotic Americans to not take this election lightly.”

Read his full remarks as prepared for delivery:

Tonight, we are honored to stand here as the parents of Captain Humayun Khan, and as patriotic American Muslims with undivided loyalty to our country. Like many immigrants, we came to this country empty-handed. We believed in American democracy — that with hard work and the goodness of this country, we could share in and contribute to its blessings. We were blessed to raise our three sons in a nation where they were free to be themselves and follow their dreams. Our son, Humayun, had dreams of being a military lawyer. But he put those dreams aside the day he sacrificed his life to save his fellow soldiers. Hillary Clinton was right when she called my son “the best of America.” If it was up to Donald Trump, he never would have been in America. Donald Trump consistently smears the character of Muslims. He disrespects other minorities, women, judges, even his own party leadership. He vows to build walls and ban us from this country. Donald Trump, you are asking Americans to trust you with our future. Let me ask you: Have you even read the U.S. Constitution? I will gladly lend you my copy. In this document, look for the words liberty and equal protection of law. Have you ever been to Arlington Cemetery? Go look at the graves of the brave patriots who died defending America — you will see all faiths, genders and ethnicities. You have sacrificed nothing and no one. We can’t solve our problems by building walls and sowing division. We are “Stronger Together.” And we will keep getting stronger when Hillary Clinton becomes our next President.

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