Hillary Clinton fires back at Donald Trump: 'I prepared to be president'

Democratic nominee Hillary Clinton made it clear she was prepared during the first presidential debate Monday night at Hofstra University.

The event got off to a fiery start, and Clinton didn't take one of her rival, Republican candidate Donald Trump's insults lightly. Trump commented about the former secretary of state being a professional politician and she instantly responded:

"Trump just criticized me for preparing for this debate. You know what else I prepared for? Being president."

Clinton, Trump face off in first presidential debate

Clinton's quip came after a previous heated exchange that erupted when she mentioned a fact-checking feature on her website. She noted the feature while challenging Trump to release his tax returns and discussing the economy.

When moderator Lester Holt tried to change gears after Clinton's comment, Trump cut him off. The GOP nominee then went on to criticize Clinton's website for giving away all of her plans to fight ISIS, saying she is providing "the enemy everything you want to do."

The debate started at 9 p.m. ET and was scheduled for 90 minutes.