CHICAGO (CBS) — Republican presidential candidate Donald Trump continued to face heated backlash Thursday for his attacks on the family of a fallen veteran, and for accepting a Purple Heart as a gift from a retired Army colonel.

Standing at the Vietnam Veterans Memorial Plaza across the Chicago River from Trump Tower, former Ald. James Balcer, a Marine veteran who received three Purple Hearts in Vietnam, said Trump accepting a Purple Heart from a campaign supporter is disrespectful, and not something that should be taken lightly.

“You cannot understand the hurt that the families go through, and what they’ve been through, to lose a loved one,” he said.

Balcer also blasted Trump for his attacks on Khizr Khan and his wife, Ghazala, after their appearance at last week’s Democratic National Convention.

“There should be civility in politics, and certain things are off-limits, and talking about the Gold Star Family members in that tone is absolutely wrong,” he said.

Khan’s son, Humayun Khan, was killed while serving in Iraq in 2004, criticized Trump for his proposal to ban Muslims from entering the U.S. if he is elected president.

Khan pulled a copy of the Constitution out of his suit pocket and offered to lend it to Trump, asking if he had ever read it.

“Look for the words ‘liberty’ and ‘equal protection of law,'” he said standing next to his wife, waving his paperpack copy of the Constitution.

“Have you ever been to Arlington cemetery?” he then asked. “Go look at the graves of brave Americans who died defending United States of America. You will see all faiths, genders and ethnicities. You have sacrificed nothing.”

Ghazala Khan kept silent as her husband spoke at the DNC, and Trump has suggested the speech was scripted by the Hillary Clinton campaign, and that Ghazala Khan did not speak because her husband wouldn’t let her as a Muslim woman.

“You look at his wife, she was standing there, she had nothing to say. She probably, maybe she wasn’t allowed to have anything to say. You tell me. But plenty of people have written that. She was extremely quiet. And it looked like she had nothing to say. A lot of people have said that,” Trump said.

Jim Frazier, whose son was killed in combat in Afghanistan, said Trump’s comments are hurtful to veterans and their families.

“We have holes in big our hearts. We have a pain; immeasurable sadness. That never goes away, and what we fear the most is that our sons and daughters and husbands and wives who were killed are forgotten,” he said.

Former Gov. Pat Quinn said Trump’s comments about the Khan family show his attitude towards veterans and military families.

“I really feel that Donald Trump owes an apology to the Khan family, and to all the Gold Star Families in America, and if you can’t honor them, I don’t know how you can put together a program that takes good care of all the veterans,” he said.

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