U.S. Army Captain Humayun Khan was killed in Iraq in 2004 when a car blew up after he told his troops to stand back. He took 10 steps forward to check out the suspicious vehicle himself, saving the lives of the soldiers he supervised.

Captain Khan’s heroism was highlighted by Hillary Clinton on July 28 at the Democratic National Convention. His father, Khizr Khan, took the stage with Khan’s mother, Ghazala Khan, and movingly described their son’s sacrifice for the United States.

At one point, Khizr Khan waved a copy of the U.S. Constitution and demanded that Republican nominee Donald Trump honor the sacrifice of his son, who was a Muslim. Khan previously told the Washington Post that he moved to America in the 1970s for “freedom and opportunity” because his native Pakistan was under military rule. Khan has continued criticizing Trump since the Convention, leading to a war of words with the Republican nominee that has earned Trump more controversy.

“Donald Trump, have you even read the Constitution? I will gladly lend you my copy,” he said. At another point in the speech, he said, “If it was up to Donald Trump, [Humayun] never would have been in America. Donald Trump consistently smears the character of Muslims. … He vows to build walls and ban us from this country.”

Who is Humayun Khan?

Here’s what you need to know:

1. Humayun Khan Was Born in the United Arab Emirates But Came to the United States as a Child & Taught Disabled Children How to Swim

The San Francisco Chronicle described Humayun Khan as “a careful and deliberate young man.” Humayun was raised in Maryland, where he went to high school. He was described as “affable” and “driven,” said The Chronicle. In high school, Humayun gave swimming lessons to disabled children and showed a unique sense of early responsibility, his father told The Washington Post.

Although he was born in The United Arab Emirates, Humayun Khan was of Pakistani heritage. The press release about his funeral said, “His colleagues and superiors remembered him for his courage, honesty, sense of humor and grace while in the field, even under pressure. Captain Khan’s colleagues eulogized his exemplary services and praised him for the leadership he provided to his troops.” The Washington Post reported Khan had a girlfriend at the time he died, Irene Auer, 24, of Amberg, Germany.

Khizr Khan said in his convention speech, referring to Donald Trump, “Have you ever been to Arlington cemetery? Go look at the graves of brave patriots who died defending the United States of America. You will see all faiths, genders and ethnicities. You have sacrificed nothing and no one.”

A Muslim chaplain spoke at the funeral about “the ethnically-diverse group that had come to pay its respects to Captain Khan,” who was described in the release as “one amongst the growing number of Pakistani Americans in the U.S. Army.” Almost 6,000 Muslims serve in the American military, with most in the Army, ABC News said in 2015. ABC said Muslims have fought for America in all major wars, including the Civil War.

2. Humayun Khan Enlisted in the U.S. Army After Graduating From the University of Virginia & Read Books on Thomas Jefferson

Humayun Khan was planning to attend law school before he enlisted in the U.S. Army, according to Vocativ. He was ultimately promoted to a captain’s rank, and was assigned to lead an infantry company in Iraq, said the news site.

According to The Chronicle, Humayun had enrolled in ROTC in college and graduated with a psychology degree. In Iraq, he served as a “counselor to soldiers” and wanted to “become an advocate for veterans” after he left Iraq, the newspaper said.

The Washington Post described how Khan reassured his mother that he would be safe. “Whenever I talked to him, I started to cry,” his mother, Ghazala Khan, recalled to the newspaper. “He always said to me, ‘Don’t worry. I’m safe.’”

Khizr Khan told The Washington Post that Humayun “was always reading books about Thomas Jefferson” and that Khizr often took Humayun to the Jefferson Memorial when he was small. According to Khan, Humayun “quoted Jefferson in his admissions essay” for college, “a line about freedom requiring vigilance,” said The Washington Post.

 

Ghazala Khan is a Gold Star mother whose son, Capt. Humayan Khan, was killed in Iraq. She joined her husband, Khizr Khan, at the Democratic National Convention.

 

3. Captain Khan Saved His Troops by Telling Them to Stay Back as He Went Forward to Investigate a Suspicious Vehicle

“Captain Khan told his troops to get back, but he went forward. He took 10 steps toward the car,” said Democratic nominee Hillary Clinton in a video introducing Khan’s father, Khizr Khan’s, convention speech. The car exploded, killing Humayun Khan, but the rest of the troops were saved because he stepped forward, said Clinton.

According to a U.S. Department of Defense press release, Captain Humayun S. M. Khan, 27, of Bristow, Virginia, died June 8, 2004, in Baquabah, Iraq, “after a vehicle packed with an improvised explosive device drove into the gate of his compound while he was inspecting soldiers on guard duty.” The release says Khan was assigned to Headquarters Company, 201st Forward Support Battalion, 1st Infantry Division, from Vilseck, Germany.

According to Vocativ, 13 other American Muslims, in addition to Khan, died while serving in the U.S. military in the 10 years following the Sept. 11, 2001, terrorist attacks.

4. Khan Was Posthumously Awarded the Purple Heart & Bronze Star for His Heroics in Iraq

Humayun Khan was awarded the Bronze Star and Purple Heart posthumously, said Clinton, and he was 27-years-old when he died. “’We still wonder what made him take those 10 steps,’ Khan’s father said in a recent interview,” Clinton added. “…All those things he learned in this country kicked in. It was those values that made him take those 10 steps.”

To the Washington Post, Khizr Khan called his son a “peacemaker,” saying that, during the three months he had been in Iraq, Capt. Khan developed a program to put “Iraqi civilians to work for $5 an hour patrolling the streets of Baquba under the U.S. Army.” Capt. Khan recalled to The Post that his son said to the Iraqis, “‘We’re here not to hurt you but to help you.’”

Arlington Cemetery says that Capt. Khan “was laid to rest with full military honors. Captain Khan was a Pakistani American who served in the U.S. army as an ordnance officer, being the senior-most community member to die in Iraq.”

5. Khizr Khan Called Donald Trump ‘an Ignorant, Divisive Manipulator’ & Said he Has a ‘Black Soul’ & Ghazala Khan Wrote an Op-Ed Criticizing Trump

Khizr Khan, who came to America from Pakistan in the 1970s, told Vocativ, “Muslims are American, Muslims are citizens, Muslims participate in the well-being of this country as American citizens.”

Khizr Khan, 65, who lives in Virginia, told The San Francisco Chronicle, “This is our country too. This is not only Donald Trump’s country. He is an ignorant, divisive manipulator, and through my message I wish to convey to him and to all Muslim Americans: This is our country too.”

Trump has used Twitter to respond in part:

Khizr Khan is a legal consultant who moved his family to the United Arab Emirates and then to Boston, where he attended a master’s program in law at Harvard University, before settling in Virginia. The NBC affiliate in Khan’s hometown reported that Khan said “he cherishes the values of this country and wants to provide a voice toward the message of unity, a focus of Clinton’s campaign.”

The station quoted Khan as saying that Humayun would be disturbed, if he were still alive, “because of the division that one candidate continues to cause. And I say this in his spirit – he would stand with the most qualified, most uniting, most putting us together candidate versus the candidate that continues to tear us apart.”

ABC News says Trump is causing new controversy by saying in an interview that “he had in fact sacrificed by employing ‘thousands and thousands of people.’ He also suggested that Khan’s wife didn’t speak because she was forbidden to as a Muslim and questioned whether Khan’s words were his own.” A hashtag #TrumpSacrifices erupted on Twitter, with critics mocking Trump for supposed sacrifices.

On Sunday, July 31, Khan doubled down on his criticism of the Republican nominee. He told CNN that Trump has a “black soul,” and said he hopes Trump’s family will “teach him some empathy.”