The Senate Finance Committee has asked the Internal Revenue Service (IRS) to hand over records, including donor lists, relating to Muslim charities and foundations, the paper said on Wednesday, citing documents and officials.
The request is a rare and an unusually broad use of the committee's power to obtain private records held by the government, the paper added.
IRS officials say they expect to comply with the request because it falls within the panel's statutory authority, according to The Post.
The request includes leadership lists, financial records, applications for tax-exempt status, audit materials and the results of criminal investigations.
"Government officials, investigations by federal agencies and the Congress and other reports have identified the crucial role that charities and foundations play in terror financing," Committee chairman Charles Grassley, an Iowa Republican, and the panel's senior Democrat, Montana Senator Max Baucus, wrote in a 22 December letter to the IRS.
"The Muslim community would view this as another fishing expedition solely targeting Muslims in America. Are they now going to start a witch hunt of all the donors so that Muslims feel they're going to be targeted once more based on their charitable giving"
Spokesman, Council on American-Islamic Relations
"We have a responsibility to carry out oversight to ensure charities, foundations and other groups are abiding by the laws and regulations, to examine their source of funds, and to ensure government agencies, including the IRS, are policing them and enforcing the law efficiently and effectively," the letter added.
Muslim leaders and attorneys for charities say the government's investigation has tarnished their reputations and chilled financial support for groups that provide humanitarian support in the Middle East and elsewhere.
"The Muslim community would view this as another fishing expedition solely targeting Muslims in America," Ibrahim Hooper, spokesman for the Council on American-Islamic Relations said.
"Are they now going to start a witch hunt of all the donors of these now closed relief organisations, so that Muslims feel they're going to be targeted once more based on their charitable giving," he added.
Committee staff said the investigation was based not on ethnicity or religious affiliation but rather on concerns that the groups might have ties to terror suspects or their supporters.
"This is not a fishing expedition targeting Muslims," one Senate aide said.
"All the groups we're looking at are suspected of having some connections to terrorism or of doing propaganda for terrorists. We're not presuming anybody's guilty."