Menendez: Allegations are false

Sen. Robert MenendezRobert (Bob) MenendezOvernight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions Poll finds little support for Menendez reelection Judge tells Menendez lawyer to 'shut up' MORE (D-N.J.) on Wednesday defended his relationship with a political donor under investigation by the FBI as being ethically sound.

In a statement, Menendez’s office described Dr. Salomon Melgen as “a friend and political supporter” of the senator’s for many years.

A team of FBI agents stormed Melgen’s Florida business on Tuesday, according to a report in The Miami Herald. Melgen is suspected of providing free trips and even underage Dominican Republic prostitutes to Menendez, according to a complaint lodged with the Justice Department by a Washington D.C. watchdog group last year.

Menendez denied those allegations, saying they were manufactured by the conservative media website The Daily Caller ahead of his election last November.

“Sen. Menendez has traveled on Dr. Melgen’s plane on three occasions, all of which have been paid for and reported appropriately,” said Menendez’s office in a statement. “Any allegations of engaging with prostitutes are manufactured by a politically motivated right-wing blog and are false.”

Speculation about the ethics of Menendez’s relationship with Melgen, who has donated to the campaigns of multiple congressional Democrats and Republicans, arose last fall after a claim by the chairman of the Middlesex County Republicans.

Melgen has let Menendez fly on his private plane several times, and the GOP chairman asked the Senate Ethics Committee to investigate whether the lawmaker properly disclosed the private flights on his official financial disclosure forms.

Menendez’s office has fervently denied the allegations.

Flight records and financial documents obtained by The Hill show that the New Jersey Democrat either did not fly or has properly reimbursed at least three of the four flights questioned in the letter sent to the Senate Ethics panel.

It is unclear whether the FBI’s investigation of Melgen is targeting him for outstanding back taxes, his political contributions to Menendez and other lawmakers, or allegations over engaging with prostitutes.

Melgen has an outstanding IRS lien of $11.1 million in back taxes owed from a three-year period and had previously been subjected to a $6.2 million lien that was released in 2011, according to the Herald.

On Wednesday, the watchdog group Citizens for Responsibility and Ethics in Washington (CREW) released 56 pages of e-mail exchanges from 2012 between the group’s research director and a man who went by the name “Peter Williams.” Williams alleged to have first hand knowledge that Menendez had engaged with underage prostitutes in the Dominican Republic at a luxury resort owned by Melgen.  CREW declined to publicly release the e-mails and instead referred the matter to ABC News and the DOJ because the watchdog could not verify that the allegations were true.

But news of the allegations did not surface until days before Menendez’s re-election in November when the conservative website The Daily Caller published an interview with Dominican prostitutes who claimed to have met Menendez at Melgen’s resort. The prostitutes said Menendez paid them for sex, but the New Jersey lawmaker's office has repeatedly denied the accusations and characterized them as political in nature.

On Tuesday, Senate Majority Leader Harry ReidHarry ReidThe Memo: Trump pulls off a stone-cold stunner The Memo: Ending DACA a risky move for Trump Manchin pressed from both sides in reelection fight MORE (D-Nev.) also defended Menendez, who is slated to take over the chairmanship of the Senate Foreign Relations Committee following Sen. John KerryJohn Forbes KerryBringing the American election experience to Democratic Republic of the Congo Some Dems sizzle, others see their stock fall on road to 2020 The Hill's 12:30 Report MORE’s (D-Mass.) appointment to be Secretary of State.

“I always consider the source,” Reid said in a press conference, referring to The Daily Caller. “All anyone here has to look at is the source where this comes from. It’s a source that has brought up a lot of non-issues.”

The Daily Caller told The Hill that it stands by its articles.

“We stand by our reporting and we look forward to reporting on the further details of the investigation as they emerge,” said Nicole Roeberg, a spokeswoman for the website.

The Melgen family is a frequent financial contributor in Florida politics, having given money to prominent members of Congress, including Sen. Bill NelsonClarence (Bill) William NelsonDem asks airlines to cap airfares ahead of Hurricane Maria Trump encourages Rick Scott to run for Senate Overnight Regulation: House moves to block methane rule | Senators wrestle with allowing driverless trucks | EPA delays toxic waste rule MORE (D) and Reps. Debbie Wasserman Schultz (D), Joe GarciaJoe GarciaFlorida Dems hosting fundraiser for GOP lawmaker Freshman Curbelo wins reelection in Fla. LGBT Republican groups campaigning for Curbelo in Fla. MORE (D), Ileana Ros-Lehtinen (R) and Mario Diaz-Balart (R).

Melgen was honored at the U.S. Capitol on Nov. 20, 2010 by the Dominican American National Roundtable's National Council Leadership Summit, according to a press release distributed by PR Newswire that month.

The release states, "In his introduction, Sen. Menendez highlighted their close and longstanding relationship, his admiration for Dr. Melgen's perseverance in pursuit of the American dream and his dedication to helping others through his many, mostly anonymous charitable efforts." Melgen is listed as the source of the press release.

Bob Cusack contributed to this article, which was updated at 5:30 p.m.