The FBI is considering whether to open an investigation into allegations that followers of a New York City rabbi made illegal campaign contributions to U.S. Rep. Michael Grimm, according to a law enforcement official.

Followers of Rabbi Yoshiyahu Yosef Pinto, an influential figure in Israel with a headquarters in Manhattan, raised hundreds of thousands of dollars for Grimm when he first ran for office in 2010, according to campaign records. Some donors have since said that they broke rules to donate more cash to the Republican's campaign than allowed by law.

Pinto hasn't commented publicly, but former U.S. Rep. Anthony Weiner, a Democrat who had been close to the rabbi, said in interviews with several media outlets Friday and Saturday that Pinto approached him in the fall of 2010 to complain that Grimm had extorted him for the money.

Weiner, who resigned last year amid a scandal over sexually explicit texts and Twitter messages, told the political newspaper Roll Call that he didn't know if the allegations were true, but reported them to the FBI anyway. He declined to discuss in detail why the rabbi felt he had been threatened.

"I can confirm the Rabbi did bring allegations to me and I can confirm that I turned them over to the FBI immediately," Weiner told Roll Call. Weiner didn't immediately respond to an interview request from the AP.

A law enforcement official confirmed Saturday that Weiner had contacted the bureau about Pinto's allegations in 2010.

The official also confirmed that the FBI is gathering information and considering whether or not to open a formal investigation into fundraising for Grimm by Pinto's followers and associates.

The official spoke on condition of anonymity because the investigation is incomplete.

Grimm's representatives didn't immediately respond to phone calls and emails from The Associated Press on Saturday, but he released statements to several newspapers calling the allegations completely false.

"These allegations are so profoundly absurd that they serve as proof of the coordinated, Democratic smear campaign designed to recruit a stronger opponent to challenge me," Grimm said.

He also accused Weiner of making up the story about going to the FBI.

Grimm told the Advance, a newspaper on Staten Island, that if Weiner really did hear such an explosive charge in the fall of 2010, he surely would have gone public to keep the congressional seat in the borough, then held by a Democrat, from falling into Republican hands.

"No rational person would believe these politically motivated fantasies," he said.

It isn't clear whether Weiner's report to the FBI in 2010 resulted in any action. Grimm is a former FBI agent who spent a decade working for the bureau before leaving to pursue private business interests.

The FBI is already pursuing a related investigation involving Pinto's congregation.

Last year, Pinto accused one of his former aides, Ofer Biton, of stealing funds from the congregation and then conspiring with a public relations executive, Ronn Torossian, to blackmail him into making more payments to put a stop to unfavorable stories about him in the Jewish and Israeli press.

Both Biton and Torossian have denied any wrongdoing. Their lawyers say the allegations were fabricated, but the FBI has spent several months interviewing witnesses and records.

During the period when Pinto claims that Biton and Torossian were demanding money, the pair were also prolifically raising funds for Grimm's campaign.

Both men appeared at several fundraising events for Grimm, and the congressman has acknowledged that Biton was instrumental in helping him make connections with Pinto's followers. In an earlier interview with the Advance, he said that Biton arranged meetings with Pinto's followers, many of whom are Israelis, and kept lists of potential donors.

Torossian also raised money for Grimm, who campaigned, in part, on a pledge to be a strong supporter of Israel.

Grimm has repeatedly denied any knowledge that Pinto's supporters were breaking the law to assemble his donations.

Pinto's followers had also raised large sums of money for Weiner, a liberal Democrat.

The allegations by Rabbi Pinto's followers that they evaded campaign finance rules to funnel money to his campaign were first reported in January by The New York Times.