Illinois Congresswoman Tammy Duckworth, a veteran of the Iraq War, had a message for Donald Trump on Tuesday after he boasted about receiving a Purple Heart the “easy” way, when it was given to him by a veteran at a rally.

“[Donald Trump], this is how one usually looks when you are awarded the Purple Heart. Nothing easy about it,” Duckworth said on Twitter. The tweet included an image of Duckworth in a hospital bed when she was recovering from her injuries, which she suffered when a helicopter she was flying was shot down in Iraq. Duckworth lost both of her legs in the attack.

Trump said the heart he received Tuesday was authentic, but NBC News reported that it was a replica. “A man came up to me and he handed me his Purple Heart,” Trump said at the Ashbury, Virginia, rally. “I always wanted to get the Purple Heart. This was much easier, but I tell you it was such an honor.”

Following his remarks, Duckworth launched a petition demanding Trump apologize.

“Donald Trump shows a lack of understanding and appreciation for the sacrifices of our service members and their families,” Duckworth said. “I’m outraged that anyone seeking to be Commander in Chief of this great nation would show so little respect for our troops.”

Trump has also been under fire for his attacks on the family of a US Army captain, whose father, Khizr Khan, spoke against the candidate last week at the Democratic National Convention in Philadelphia. His dispute continues as several Republican politicians, including Sen. John McCain, have condemned the GOP nominee for his remarks.