A group has sent a nearly 1,400-page filing to the Internal Revenue Service demanding that it “retroactively revoke” the American Israel Public Affairs Committee’s tax-exempt status.

The group, known as the Institute for Research: Middle Eastern Policy, or IRmep, claims in the filing that AIPAC's original application for tax-exempt status contains “fraudulent representations and omissions.”

The group also noted that the pro-Israel lobbying organization has been investigated by the FBI and is currently in a civil suit over the acquisition and movement of classified information. The filing argues that these activities show AIPAC does not qualify as a “social welfare” organization.

IRmep’s leader called in to a radio show on NPR in January where IRS Commissioner Doug Shulman was the guest and asked about some of the charges. “If a charity is breaking the tax law, is engaged in activities that they are not supposed to be engaged in, we certainly will go after them,” he responded, according to the group. “Every year we pull 501(c)(3) charity status from a number of charities. We’ve got thousands of audits going on regarding charities, and so we don’t hesitate to administer the tax laws and make sure that people are following the rules.”

AIPAC did not respond to a request for comment.

The group has endured its share of controversies over the years, but it nevertheless remains politically influential. However, AIPAC has also seen its influence as a lobbyist in Washington for Israeli causes challenged in recent years by more liberal groups such as J Street, and the IRS filing could further erode its support and imperil its tax status. IRmep is another group that has been battling AIPAC, and the IRS filing is the most recent salvo in that campaign.

The IRS has increasingly been on the receiving end of letters from various groups demanding that the tax-exempt status of groups opposed to their ideology or political or religious leanings be investigated or revoked. As the IRmep filing shows, that trend shows no signs of slowing down anytime soon.