FBI probing allegations Sen. Menendez patronized prostitutes in Dominican Republic The two, who spoke on the condition of anonymity to discuss an active investigation, said FBI agents are following leads provided by an unknown tipster. In a series of e-mails with the FBI, the tipster alleged that the doctor, Salomon Melgen, had made prostitutes available to Menendez while he was staying at his friend's resort home in the Dominican Republic. The tipster, in particular, mentioned young prostitutes and prostitution parties. The FBI agents are also examining the role Menendez played in advocating for a port security contract in the Dominican Republic that would benefit Melgen, two people familiar with the case said. Menendez has urged U.S. officials to put pressure on the Dominican government to enforce the dormant contract, saying enhanced port security is important for interdicting drug trafficking. Melgen is an investor in the company holding the contract. FBI spokesman Michael Leverock, of the bureau's field office in Miami, declined to comment for this article. Menendez has vehemently denied the prostitution allegations, calling them false "smears." "As we have said all along, Senator Menendez welcomes any review because his actions have been appropriate, and we believe the facts will confirm that," a Menendez aide said Friday. The staff member, who spoke on the condition of anonymity, said the senator's efforts on behalf of the port deal were appropriate. "The senator has had a long history of advocating for increased port security across the world," the aide said. Melgen and his attorneys declined to comment on any criminal investigation. The relationship between Menendez and Melgen has come under intense scrutiny in recent weeks. Menendez acknowledged this month that he had failed to properly disclose two trips he took in 2010 on Melgen's private plane to Melgen's villa, near the resort of Casa de Campo. The senator said he wrote Melgen a personal check for $58,500 to reimburse him for the plane rides last month. The Senate Ethics Committee is investigating the matter. Separately, Melgen is under criminal investigation over allegations of Medicare fraud. Three people with knowledge of the probe disclosed this week that it focuses on whether Melgen defrauded the government by overcharging Medicare for millions of dollars in eye injections and billing the government for treatments that were unnecessary. The FBI and the Department of Health and Human Services" Office of Inspector General raided Melgen's Palm Beach eye clinic Jan. 29, searching records and collecting boxes of documents. The raid came days after the tipster's e-mail exchange with the FBI was posted anonymously on a Web site.