A federal judge yesterday ordered that an Egyptian man stay in jail after prosecutors said he could face a third set of charges in a sprawling investigation into whether Islamic charities in Northern Virginia were financing terrorist organizations.

Soliman S. Biheiri, 52, is the only person convicted in connection with the charity probe; last year, a federal jury in Alexandria found him guilty of lying under oath on his application for U.S. citizenship. Last month, Biheiri was indicted again and charged with lying to federal agents about ties to terrorists.

Prosecutors say Biheiri concealed his connections to Mousa Abu Marzook, a leader of the Islamic Resistance Movement, or Hamas, who has been designated a terrorist by the U.S. government. Biheiri also is accused of hiding his dealings with Sami al-Arian, a Florida college professor charged with being a leader of the terrorist group Palestine Islamic Jihad.

At a detention hearing for Biheiri yesterday, Assistant U.S. Attorney David Laufman said Biheiri could face "additional and possibly more serious charges." He declined to elaborate, but he told a federal judge that Biheiri should stay in jail because his terrorist ties, access to funds from overseas and lack of U.S. ties would make him likely to flee. Biheiri, whose estranged wife and children live in Reston, finished his first prison term on the immigration conviction June 14 but now is facing deportation proceedings.

U.S. Magistrate Judge Barry R. Poretz ordered Biheiri detained until his trial on the second set of charges, citing Biheiri's overseas travel, family ties to Egypt and "the nature and circumstances of the charges."

Biheiri's attorney, Danny C. Onorato, called Biheiri a "legitimate businessman" and blasted the government's case as weak. He accused prosecutors of harassing Biheiri with what he called "an abuse of prosecutorial discretion."

"But for the fact that he is Islamic, Mr. Biheiri would not be here before this court," Onorato said.

Laufman responded: "The notion that the only reason this defendant is here before this court is because of his race and ethnicity is wrong and beneath contempt."

Biheiri founded BMI Inc., an investment firm that adhered to Islamic principles, in New Jersey in 1986.

Prosecutors said Islamic charities based in Northern Virginia and sponsored by the Saudi Arabian government invested nearly $4 million in the company. At Biheiri's sentencing on his earlier conviction in January, prosecutors said the government believes that Biheiri was dispatched to the United States to start a financial organization as part of a plan to finance and support terror organizations.

The cluster of Islamic charities is the subject of a sprawling federal probe into allegations of tax fraud and other improprieties, according to court papers and testimony. The investigation drew widespread attention in March 2002 when federal agents raided companies operating in the 500 block of Grove Street in Herndon and elsewhere in Northern Virginia. The charities have strongly denied any terrorist links.