WASHINGTON — Federal investigators looking into Rep. Matt Gaetz's relationships with young women have examined whether any federal campaign money was involved in paying for travel and expenses for the women, a person briefed on the matter said.

Investigators are examining whether the Florida Republican engaged in a relationship with a woman that began when she was 17 years old and whether his involvement with other young women broke federal sex trafficking and prostitution laws, according to that source and another person briefed on the matter.

Investigators are also pursuing allegations from witnesses and other evidence that Gaetz may have used cash and drugs in his dealings with young women, the sources said, according to a CNN report.

Gaetz has denied the allegations and has tried to portray the sex trafficking investigation as connected to an alleged extortion plot against him. People briefed on the matter say investigators don't believe the extortion claims are linked to the separate alleged sex crimes investigation of Gaetz that has been ongoing for months.

The Gaetz investigation is still in its early stages, according to sources familiar with the matter. An attorney for Gaetz had no comment.

The investigation of Gaetz began in the closing months of the Trump-era Justice Department under then-Attorney General William Barr and was initially part of a broader probe into trafficking allegations against another Florida politician, Joel Greenberg.

The New York Times reported Thursday evening that investigators believe Greenberg recruited multiple women online for sex and that he introduced the women — who received cash payments — to Gaetz, who had sex with them too, according to three people with knowledge of the encounters.

The Times reviewed receipts from Apple Pay and the mobile payment Cash App that show payments being made from Gaetz to Greenberg and then to one of the women, along with a payment from just Greenberg to a separate woman. The women had told their friends the payments were for sex with Gaetz and Greenberg, two people familiar with the conversations told the newspaper.

Gaetz and Greenberg had told the women to meet at specific places and times during encounters in 2019 and 2020 along with the amount of money they'd be willing to pay, according to interviews and messages reviewed by the Times.

Under the law, sex among adults can cross the line into criminal sex trafficking if one person uses force, threats, fraud or coercion and there's some form of payment involved. The federal sex trafficking charge that Greenberg currently faces — for trafficking a child — is a slightly different offense with the potentially harsher consequence of a minimum 10 years in prison if he were convicted.

So far, prosecutors have revealed little specific details in court papers against Greenberg. His indictment alleges that he knew a child between 14 and 17 years old would be forced to engage in sex in exchange for anything of value and enticed the child across state lines. He has pleaded not guilty.

Gaetz denied to the Times ever paying for sex, and told Fox News' Tucker Carlson on Tuesday, "Providing for flights and hotel rooms for people that you're dating who are of legal age is not a crime."

In a statement to the Times, Gaetz's office said: "Matt Gaetz refutes all the disgusting allegations completely." Greenberg's attorney declined to comment to the Times.

Additionally, information that may connect Gaetz to a fake ID scheme at the center of the case against Greenberg, was presented to federal investigators in a meeting early last year, according to two other people familiar with the matter.

In the meeting, which has not been previously reported, a witness provided evidence linking Gaetz to Greenberg, the former tax collector in Seminole County, Florida, who was arrested last year on charges that include sex trafficking of a minor and fabricating fake IDs.

Greenberg is set to go to trial later this year on the ID and sex trafficking charges, as well as charges that he stalked a former political rival. News of the meeting offers details about the Justice Department's early awareness of the congressman's relationship with Greenberg.

According to one of the people familiar with the matter, an employee at the tax collector's office saw Greenberg and Gaetz on internal office surveillance video looking through driver licenses on a weekend evening.

In a text message exchange shared with CNN that the source said was between Greenberg and the employee, Greenberg confirmed he was in the office "showing congressman Gaetz what our operation looked like."

That witness shared the information with prosecutors from the local US attorney's office and US Secret Service agents investigating Greenberg's case in January 2020, the person familiar with the matter said.

The Secret Service regularly investigates federal financial crimes. There is no indication that the IDs seen being handled in the video were used for unlawful purposes.

As the head of the tax collector's office, Greenberg had access to driver licenses that people would surrender to the office. According to court documents in his case, Greenberg allegedly used surrendered licenses to create fake IDs.

In an August indictment, federal prosecutors accused Greenberg of unlawfully accessing a motor vehicle database to obtain and use the personal information of people including some who Greenberg "was engaged in 'sugar daddy' relationships" with.

He is also accused of sex trafficking a child between the ages of 14 and 17 years old and unlawfully obtaining the photograph and driver identification number of that child.

The two people familiar with the matter said the congressman's weekend visit to the office took place in 2019. — CNN