NEW YORK - Under heavy guard, a Guantanamo Bay detainee walked into a civilian U.S. courtroom for the first time yesterday, underscoring the Obama administration's determination to close the Cuban prison and hold trials here despite Republican alarms about bringing terror suspects to America.

Ahmed Ghailani, a Tanzanian accused in two American Embassy bombings a decade ago, pleaded not guilty - in English - in a brief but historic federal court hearing that transported him from open-ended military detention to the civilian criminal justice system.

President Obama has said that keeping Ghailani from coming to the United States "would prevent his trial and conviction." Taking a drastically different stance, House Republican leader John A. Boehner of Ohio labeled yesterday's move "the first step in the Democrats' plan to import terrorists into America."

Ghailani, accused of being a bomb-maker, document-forger, and aide to Osama bin Laden, was brought to New York to await trial in connection with al-Qaeda bombings that killed 224 people - including 12 Americans - at the embassies in Tanzania and Kenya in 1998.

U.S. marshals took custody of Ghailani from his military jailers and transferred him to a federal lockup in lower Manhattan that currently holds financial swindler Bernard Madoff, and once held mob scion John "Junior" Gotti and Sheikh Omar Abdel-Rahman, the blind terror leader.

Short and slim with a wispy goatee, Ghailani walked into the courtroom without shackles or handcuffs.

He listened at times through an interpreter but then removed the headphones and appeared to understand what was said in English.

Asked by the judge if he wanted her to "read this big fat indictment," he conferred with his lawyer, said it was not necessary, and made his plea: "Not guilty."

Ghailani's attorney, Scott L. Fenstermaker, declined comment after the hearing.

"We are ready to proceed in the case," declared Assistant U.S. Attorney David Raskin, who said there was "voluminous" evidence to be shared among attorneys.

U.S. District Judge Loretta A. Preska acknowledged Ghailani's U.S. military lawyers, Marine Col. Jeffrey Colwell and Air Force Maj. Richard Reiter, who were seated in the courtroom but were not representing him at the hearing.

"Anything you can do to help him transition to the civilian courts will be greatly appreciated," she said.

Ghailani's trial will be an important test case for Obama's plan to close the detention center at Guantanamo in seven months and bring some of the terror suspects there to trial.

Attorney General Eric H. Holder Jr. said: "The Justice Department has a long history of securely detaining and successfully prosecuting terror suspects through the criminal justice system, and we will bring that experience to bear in seeking justice in this case."

Though the bombings were a decade ago, "for us, it's like yesterday," said Sue Bartley, a Washington-area resident who lost her husband, Julian Leotis Bartley Sr., then U.S. consul general to Kenya, and her son, Julian "Jay" Bartley Jr.

"The embassy bombings were a precursor to 9/11," she said. "And even though we know that an American embassy located in any country is American soil, I don't think people really understand that."

The U.S. response to the Sept. 11 attacks - including the opening of the Guantanamo detention center - could also complicate Ghailani's case, as defense lawyers are likely to mount legal challenges based on the circumstances of his capture, detention, and treatment over the years.

Justice Department officials would not say yesterday what would be done with Ghailani if he was acquitted, but in past cases a noncitizen defendant would be turned over to immigration authorities for deportation.

There will also be political challenges to Ghailani's trial.

Congressional Republicans have repeatedly contended that transferring terrorist suspects to U.S. soil will threaten public safety. The Guantanamo issue has seemed one of the few issues falling the Republicans' way, as polls suggest that most Americans want to keep the Cuba-based prison operating.

But if Ghailani can be handled without serious incident, the GOP argument may lose steam and Congress may rethink its refusal to fund the closing of Guantanamo. The move also could bolster Obama's efforts to persuade other nations to accept some detainees from the prison.

U.S. officials contend that Ghailani began a terrorist career on a bicycle delivering bomb parts and rose through the al-Qaeda ranks to become an aide to bin Laden.

After the Aug. 7, 1998, bombings at U.S. embassies in Nairobi, Kenya, and Dar es Salaam, Tanzania, Ghailani worked his way up the al-Qaeda ranks, according to military prosecutors.

He was categorized as a high-value detainee by U.S. authorities after he was captured in Pakistan in 2004, and he was transferred to the detention center in Cuba two years later.

Palau May Take Uighurs

The Obama administration is nearing agreement with the remote South Pacific island nation of Palau to resettle a group of Chinese Muslims held at the Guantanamo Bay detention center, the Associated Press has learned.

As they attempt to fulfill President Obama's order to close the Guantanamo facility by early next year, administration officials are looking to Palau to accept some or all of the 17 Uighur detainees due to fierce congressional opposition to releasing them on U.S. soil, officials said.

A federal judge last year ordered them released into the United States after the Pentagon determined they were not "enemy combatants." An appeals court halted the order, and they have been in legal limbo since.

The United States will not send the Uighurs back to China for fear they will be tortured or executed.

Three U.S. officials familiar with the situation said, however, that Palau was now a prime candidate for

their relocation.

Palau, with a population of about 20,000, is an archipelago of eight main islands plus more than 250 islets that is best known for diving and tourism and

is about 500 miles east of the Philippines in the

Pacific Ocean.

- Associated PressEndText