Soliman S. Biheiri, the only person convicted in a broad probe into whether Islamic charities in Northern Virginia were financing terrorist organizations, pleaded guilty yesterday to illegally possessing and using a U.S. passport to enter the United States last year.

After his plea in U.S. District Court in Alexandria, Biheiri, 52, went on trial on a separate charge that he lied to federal agents about his alleged ties to known terrorists.

Biheiri, who founded the former investment firm BMI Inc., is accused of concealing his business and personal connections with Mousa Abu Marzook, a leader of the Islamic Resistance Movement, or Hamas. Marzook was designated a terrorist by the U.S. government in 1995.

In May, Biheiri was indicted by a federal grand jury on three counts, including a charge that he lied about his alleged dealings with Sami al-Arian, a Florida college professor accused of being a leader of the terrorist group Palestine Islamic Jihad. That count of the indictment was dismissed last week.

In his opening statement yesterday, Assistant U.S. Attorney David Laufman laid out for the jury what he said were Biheiri's extensive business dealings with Marzook, including some after Marzook was officially labeled a terrorist by the U.S. government. The prosecutor said Biheiri lied to federal agents last year about his relationship with Marzook to cover up his connections to a known terrorist.

"This case is about . . . the consequences of not telling the truth," Laufman told the jury.

Biheiri's attorney, Danny C. Onorato, called the allegations "extremely inflammatory" and told the jury that the case is not about Hamas or Marzook but about whether his client made a false statement to officials.

"This case is misguided and wrong," said Onorato, who explained what he said were years of legitimate business dealings between Biheiri and other Muslim investors such as Marzook.

"Mr. Biheiri had no reason to downplay any relationship with Mr. Marzook," Onorato said.

Last year, Biheiri, a native of Egypt, was convicted of lying under oath on his application for U.S. citizenship. In January, he was sentenced to one year in prison.

Prosecutors have alleged that Islamic charities based in Northern Virginia and sponsored by the Saudi Arabian government invested nearly $4 million in BMI. At Biheiri's sentencing, prosecutors said the government believes that Biheiri was dispatched to the United States to start a business as part of a plan to finance and support terror organizations.