Rep. Matt Gaetz (R-Fla.) doubled down Friday night, saying he's not "going anywhere," and vowing, "I have not yet begun to fight," amid a federal investigation into sex trafficking allegations.

What he's saying: “I’m built for the battle, and I’m not going anywhere,” Gaetz, who denies the allegations, said during a Women for America First event at the Trump National Doral Miami resort.

• Gaetz has not been charged with any crimes and has repeatedly denied allegations of being sexually involved with a 17-year-old and claims that he shared naked images of women with other Congress members.
• He told Axios in an interview last month that the investigation is "rooted in an extortion effort against my family for $25 million."
• “The smears against me range from distortions of my personal life, to wild — and I mean wild — conspiracy theories," Gaetz said Friday.
• "I won’t be intimidated by the lying media, and I won’t be extorted by a former DOJ official and the crooks he is working with. The truth will prevail,” he added, speaking to The Women for America First group.

The big picture: The House Ethics Committee announced earlier Friday it has launched a probe into the Florida congressman.

• The panel said it is aware of allegations that Gaetz "may have engaged in sexual misconduct and/or illicit drug use, shared inappropriate images or videos on the House floor, misused state identification records, converted campaign funds to personal use, and/or accepted a bribe, improper gratuity, or impermissible gift."

Go deeper: GOP Rep. Adam Kinzinger calls for Rep. Matt Gaetz to resign