Washington - Republican Donald Trump told a motorcycle rally on Sunday that people in the US illegally often were cared for better than the nation's military veterans, without backing up his allegation."Thousands of people are dying waiting in line to see a doctor. That is not going to happen anymore," Trump told veterans gathered in front of the Lincoln Memorial as part of the annual Rolling Thunder event, which brings thousands of motorcyclists to Washington each Memorial Day weekend.Trump has repeated his comparison of the treatment of immigrants and veterans frequently during the campaign. Congress and many states have written an assortment of laws and policies designed to restrict government services to people living in the country illegally.Prisoners of warThe Veterans Affairs Department, meanwhile, has come under criticism and congressional scrutiny for a number of failures, from cutting off benefits of thousands of veterans who were wrongly declared dead to chronically long wait times for medical services at VA health care sites. As many as 40 patients died while awaiting care at the Phoenix VA hospital alone.The Rolling Thunder event is organised to draw attention to veterans' issues and dedicated to remembering prisoners of war and service members missing in action."We're with you 100%," Trump told the crowd.Trump, now the presumptive Republican nominee for president, angered veterans last year when he said he liked "people who weren't captured" in wars. That had been a dig at Senator John McCain, R-Ariz., the party's 2008 nominee, who had been captured and held for more than five years during the Vietnam War after his plane was shot down. Trump claimed that McCain was a "war hero because he was captured."Trump quickly tried to walk back the comment but has refused to apologise to McCain.Drew scrutinyMany veterans groups were furious, but since then Trump has worked to try to repair the damage. He frequently honours veterans at his rallies and he has come out with a plan to overhaul the Department of Veterans Affairs. He also held a fundraiser for veterans' causes in place of an Iowa debate that he skipped.Still, Trump, who avoided the draft through a series of deferments, drew scrutiny for not immediately distributing the $6m he'd claimed to raise, including $1m he'd pledged himself. He is expected to hold a news conference on Tuesday to announce the names of the charities selected to receive the money.