Spy Suspect Ordered Held in Jail

W A S H I N G T O N, March, 5 -- A U.S. District Court today ordered that accused spy Robert Hanssen remain confined in jail.

The decision came after federal prosecutors argued Hanssen should be kept in jail while the case continued due to a serious risk that he might try to escape to Moscow.

Issuing the order for continued confinement in Alexandria, Va., today, U.S. District Judge Theresa Buchanan said she believed the government has an "extraordinarily strong case" against Hanssen, who could pose a serious threat to society.

She also said Hanssen posed a serious risk of flight if he was released.

Hanssen's lawyers however did not contest the confinement.

In his first public appearance since his arrest Feb. 18 in a Virginia park, Hanssen spoke only once, when Judge Buchanan asked him if he understood that he was not contesting the detention. He replied with a brief, "Yes, Ido."

The latest allegation is that Hanssen, a 25-year veteran of the FBI, may have alerted Moscow to a secret tunnel underneath the U.S. embassy in Washington D.C., which the FBI reportedly used for eavesdropping.

Russia Incensed

Reacting strongly to the reports today, Russia expressed outrage over the tunnel, which is believed to have been built in the 1970s and '80s, declaring it was unaware of the existence of the tunnel.

The denial came even as it became apparent Hanssen may have exposed the existence of the tunnel to the KGB.

In a statement released today, the Russian Foreign Ministry said if the reports were true, it would be "a flagrant violation of the recognized norms of international law that throughout the world govern relations with foreign diplomatic missions."

Officially at least, the statement suggested Moscow was unaware of the existence of the tunnel.

But ABCNEWS has learned that the U.S government knew years ago the tunnel operation had been compromised but didn't know how.

They now think that Hanssen was likely responsible. Knowledge of the tunnel could have given Russian agents a crucial advantage.