Washington - Donald Trump hit back Saturday at accusations from the father of a slain Muslim soldier that the billionaire has "sacrificed nothing" for his country, saying he had employed thousands of people.Khizr Khan - whose son died in Iraq - accused the Republican presidential nominee of vilifying American Muslims in a steely rebuke that electrified the Democratic convention on Thursday."Go look at the graves of brave patriots who died defending the United States of America," Khan said to Trump."You will see all faiths, genders and ethnicities. You have sacrificed nothing and no one."Trump brushed off Khan's words in an interview with ABC News, stating that he thinks he has made "a lot of sacrifices"."I work very, very hard. I've created thousands and thousands of jobs, tens of thousands of jobs, built great structures. I've had tremendous success. I think I've done a lot."The brash billionaire has alienated many Americans with insults against immigrants, Muslims and women during his nomination campaign.Among his more controversial policy positions has been his call to ban Muslims from entering the United States and suggestions he would back profiling them.Trump also questioned whether his rival, Hillary Clinton, had been behind Khan's address, which the father said he wrote with his wife Ghazala."Who wrote that? Did Hillary's script writers write it?" Trump said in the interview, which is set to air in full on Sunday."If you look at his wife, she was standing there. She had nothing to say," Trump said, adding that "maybe she wasn't allowed to have anything to say."Clinton released a statement on Saturday defending the Khans as "the best of America"."I was very moved to see Ghazala Khan stand bravely and with dignity in support of her son on Thursday night," Clinton said."This is a time to honor the sacrifice of Captain Khan and all the fallen. Captain Khan and his family represent the best of America, and we salute them."In a late Saturday statement from the Republican's campaign, Trump praised Captain Khan as "a hero to our country and we should honor all who have made the ultimate sacrifice to keep our country safe."However Trump rejected the claim that he had never read the US constitution."While I feel deeply for the loss of his son, Mr Khan who has never met me, has no right to stand in front of millions of people and claim I have never read the constitution, (which is false) and say many other inaccurate things," Trump said.Trump also released what he says is the transcript of the ABC interview.