(RNS) For the staff at the Holy Land Foundation for Relief and Development in Richardson, Texas, the month of Ramadan is the busiest time of the year. It's a time when many Muslim pay their zakhat, or alms -- a charitable gift equal to 2.5 percent of their net worth and one of the five pillars of Islam. On Monday, Dec. 3, that meant the staff was working late.

"We are working long hours, from 8 in the morning to midnight just to keep up with all of the donations," said John Janney, the foundation's assistant director for communication. "We have had to hire extra personnel to keep up. It's pretty much business as usual, though there is no such thing as business as usual after Sept. 11."

All of that changed at midnight on Monday, when President George Bush ordered the assets of the foundation frozen and their headquarters in Richardson was closed down, along with offices in Bridgeview, Ill., Paterson, N.J., and San Diego. The foundation, which raised $13 million in 2000, is accused of raising funds for the terrorist group Hamas.

"The Holy Land Foundation claims that the money it solicits goes to care for needy Palestinians in the West Bank and Gaza strip," Bush said Tuesday. "Money raised by Holy Land Foundation is used by Hamas to support schools that indoctrinate children to grow up to become suicide bombers."

Treasury Secretary Paul O'Neill accused the Holy Land Foundation of masquerading as a charity, "while its primary purpose is to fund Hamas. This is not a case of one bad actor stealing from the petty-cash drawer and giving the stolen money to terrorists. This organization exists to raise money in the United States to promote terror."

Holy Land Foundation president Shukri Abu-Baker denied that the group has any ties to terrorism, or that it had violated any U.S. laws. A statement released by the foundation criticized the government actions as being anti-Muslim, saying "the decision by the U.S. government to seize the charitable donations of Muslims during the holy month of Ramadan is an affront to millions of Muslim Americans who entrust charities like ours to assist in fulfilling their religious obligations." Another statement, from the Council on American-Islamic Relations and other U.S. Muslim organizations also criticized the actions, saying that they "could create the impression that there has been a shift from a war on terrorism to an attack on Islam."

In Bridgeview, Ill., a Chicago suburb with a large Muslim population, passersby watched as federal agents removed documents from the foundation's offices. Mohammad Ibra told the Associated Press that he donated $50 a month to the charity and had gotten thank-you notes from Palestinian families the foundation has assisted. "There's just no way they're involved with terrorists," Ibra told the AP. "They send medicine and clothes and money to poor people in Palestine."

The Holy Land Foundation is one of eight Muslim nonprofit groups under investigation by the Treasury Department for ties to terrorism. In early November, The Los Angeles Times reported that the groups were listed on a confidential letter sent from the Treasury Department to the attorneys general of several states. That list included six charities that collectively raised more than $29 million in 2000 -- Benevolence International Foundation of Palos Heights, Ill.; Care International Inc. of Boston, Mass.; Global Relief Foundation of Bridgeview, Ill.; Holy Land Foundation; Islamic American Relief Agency USA of Columbia, Mo.; and Islamic Relief of Burbank, Calif. The Islamic Association for Palestine of Villa Park, Ill., and the Islamic Center of Tucson, Ariz., were also listed.

Two of the groups have ties to Mousa Abu Marzook, the political leader of Hamas. Marzook was chairman of the Islamic Association for Palestine from 1988-90. He also gave $200,000 to the Holy Land Foundation in 1992. Marzook's wife is an investor in InfoCom, a Texas Internet company with ties to the foundation. InfoCom's offices were raided on Sept. 5 by federal agents and the company has been accused of illegally sending computer technology to Libya and Sudan.

Muslim charities have been under investigation since 1996, under an act passed that year that made supporting terrorism a federal crime. Grand juries in Illinois, Florida, New York and Texas have failed to issue any indictments against Muslim groups.

Last year, while it was still under investigation, the Holy Land Foundation was certified by USAID to distribute U.S. international aid. That certification was dropped before the group received any funds. The Islamic American Relief Agency received contracts to distribute more than $4 million dollars of U.S. aid to Mali in the 1990s. Those contracts were canceled in 2000 after the State Department determined they were "contrary to the national defense and foreign policy interests of the United States."

Still, there has been some evidence of links between Muslim charities and terrorist groups. One of the men convicted in the 1993 bombing of the World Trade Center was involved with the Alkifah Refugee Center, a Brooklyn charity. The investigation into 1998 bombings of two U.S. embassies found a link between Osama bin Laden and a Kenyan charity. This past March, a group of Iranian immigrants was accused of raising funds for charity and then sending the funds to a terrorist group.

For the Global Relief Foundation, news that the charity is under investigation has caused a sharp drop in contributions. Global Relief, which raised more than $4.8 million in 2000, says donations are down by 90 percent. The group denies that it is under investigation or that it has any ties to terrorists.

"We have not heard directly from Treasury, from the FBI, the State Department, the National Security Council or any other federal or local law enforcement agency about our fund-raising or about where our aid goes," says Asim Ghafoor, Global Relief spokesperson.

On Nov. 15, Global Relief filed a $125 million lawsuit against six major news organizations, saying that their "false and outrageous accounts" damaged the group's ability to raise funds. The suit, filed in U.S. District Court in Chicago, names The New York Times, The Boston Globe, Associated Press, ABC News, The (New York) Daily News, and the San Francisco Chronicle as defendants.

"As a result of loose talk and false statements from people that are not careful," said Roger Simmons, Global Relief's lawyer, "what Global Relief has experienced has been a drastic drop off in the willingness of its traditional donor base to support helping Global Relief deal with human misery.

"When that happens, people starve," Simmons added. "It's a very serious thing."

Several of the defendants have published corrections to their stories about Global Relief. ABC News reported on Sept. 23, that Global Relief, the Holy Land Foundation, and other charities, were accused of "getting funds to bin Laden," then posted a retraction on the ABCNews.com Web site. The San Francisco Chronicle reported that it had obtained documents that confirmed that Global Relief was under investigation; that story proved to be inaccurate as well.

Dr. Abdel Noureldin, an emergency room physician from Barrington, Ill., says he has found the staff at Global to be "very honest and trustworthy." Noureldin traveled with Global Relief to Ethiopia and Kosovo this past year as a volunteer on a medical team. He spent two weeks in each country working in mobile clinics and saw Global Relief's work firsthand. While in Gunagado, Ethiopia, Noureldin made house calls on people who were too sick to travel to the clinic. "You would walk in and all you would see was a rag to sleep on, some oil and wheat from the last food shipment from Global Relief."

Each morning, Noureldin said, there were 300 to 400 people waiting to be seen by doctors. Some had walked for miles. "The person who walked the longest was from 150 miles away." Many were children who had infections or other conditions caused by a lack of food and clean water.

Noureldin raised about $29,000 for the trip from friends, coworkers and from the Islamic Foundation of Villa Park, Ill. He said he promised donors that all the funds would be used for helping people; no funds would be used for overhead or other expenses. "Of the $29,000 that I raised -- $23,000 was spent on pharmaceuticals, and the rest was spent on food," Noureldin said. "My son told me that he had seen on the news that GRF was being investigated for having ties to terrorists. I don't believe it. I worked with them and what I saw was honest people working to help people."