Donald Trump Donald John TrumpBubba Wallace to be driver of Michael Jordan, Denny Hamlin NASCAR team Graham: GOP will confirm Trump's Supreme Court nominee before the election Southwest Airlines, unions call for six-month extension of government aid MORE went after a former Miss Universe in a string of early-morning tweets Friday, encouraging voters to “check out” an alleged “sex tape” of Alicia Machado, who has been on the offensive against the GOP presidential nominee all week.

During Trump’s first debate with Democrat Hillary Clinton Hillary Diane Rodham ClintonJoe Biden looks to expand election battleground into Trump country Biden leads Trump by 12 points among Catholic voters: poll The Hill's Campaign Report: Biden goes on offense MORE on Monday, she mentioned old comments he made about a Miss Universe contestant, whom he complained gained weight after she won the crown.

Machado has since given a series of interviews slamming the real estate mogul as sexist, but Trump says Clinton was “duped” into ever bringing her up.

Wow, Crooked Hillary was duped and used by my worst Miss U. Hillary flyoated her as an "angel" without checking her past, which is terrible! — Donald J. Trump (@realDonaldTrump) September 30, 2016

Using Alicia M in the debate as a paragon of virtue just shows that Crooked Hillary suffers from BAD JUDGEMENT! Hillary was set up by a con. — Donald J. Trump (@realDonaldTrump) September 30, 2016

Did Crooked Hillary help disgusting (check out sex tape and past) Alicia M become a U.S. citizen so she could use her in the debate? — Donald J. Trump (@realDonaldTrump) September 30, 2016

Machado was photographed topless for Playboy and reportedly appeared in a risqué but not nude scene on a Spanish reality TV show, in bed with a male contestant.

Fact-checkers have rated the claim that she appeared in a sex tape as "mostly false," noting that searches for "Alicia Machado Porn Star" or similar phrases turn up actual videos on pornographic websites, but all are women who aren't her.

Trump has struggled with women throughout his campaign, a weakness Clinton, the first woman nominated by a major party, has repeatedly sought to exploit.