Ellen Nakashima, Jakarta – Eleven men and a teenager met with two FBI agents at a small hotel in the remote Indonesian province of Papua on Wednesday night, expecting, they said, to be flown to the United States.

They said they had been assured by intermediaries working with the agents that in US custody they would be able to defend themselves against accusations that they murdered two American teachers on a mountain in Papua one warm August morning in 2002.

Among them was a Papuan separatist fighter, Anthonius Wamang, indicted in 2004 by a US grand jury for murder in connection with the killings. Wamang has acknowledged firing at the vehicle in which the teachers were riding on Aug. 31, 2002, but has said he thought he was shooting at Indonesian soldiers and is not sure whether the shots he fired were fatal, according to his attorney, Albert Rumbekwan.

On Wednesday night, Wamang and the others were ready to leave for the United States, suitcases packed. "Hurry, hurry," the FBI agents told them, several recounted, as they were hustled into a windowless container truck. "The plane is waiting on the runway."

After coaxing the group into the truck, the agents and a US Embassy official handed the vehicle over to Indonesian police officers and left for the airport in the small town of Timika, according to an intermediary who was present. The Indonesian police took the 12 to the local police station, where authorities interrogated them until morning.

Eight of them, including the teenager, were still in custody on Friday. Police said the government intended to charge them with the murder of Ricky Lynn Spier, 44, and Edwin Burgon, 71, who was the principal of a school run by Freeport-McMoRan Copper & Gold. The US-based company operates one of the world's largest gold and copper mines in Papua.

US officials here declined to confirm details of the arrest but acknowledged that the FBI and Indonesian authorities had been cooperating in the case.

In Washington, FBI spokesman Bill Carter said agents were in Papua at the time of the arrests but that he had no information on the assertion that they had lured the suspects with promises of a trip to the United States.

"Our understanding in this is that Indonesian authorities were planning to prosecute individuals in this case," Carter said. "We obviously reserve the right to seek extradition in the future."

The alleged bait-and-switch tactic angered human rights activists and the four men, part of the original group of 12, who were released in a province where deep-seated grievances against the central government have fueled a separatist movement. The activists charge that the Jakarta government cannot be trusted to protect the detainees.

"We were planning to end our problems from the 2002 incident in America," said one of those released, Victus Wamang, 57, the brother of the man indicted in the United States. "But right now, I'm feeling really, really sorry that I trusted these Americans. I thought that they would not deceive the Papuans. Right now, I've lost all trust in the Americans."

The case had complicated relations between the two countries. At times, US investigators were hampered by a lack of cooperation. Early on, agents were tailed by special police. But now, both sides hail the arrests as evidence of good cooperation.

An initial police report implicated the military in the killings, and US officials at the time said the evidence indicated possible military involvement. But today, both Indonesian and US officials have said that Anthonius Wamang and other members of the Free Papua Movement are guilty.

Two Papuans, Eltimus Omaleng and Willy Mandowen, who were friends with the detainees, helped the FBI negotiate with Wamang and the others. The FBI pledged that the detainees would be transferred to the United States for trial, Omaleng said. FBI agents told him "to make this promise to the people," Omaleng said. "This problem would be solved by US law."

Mandowen and Omaleng arranged for the surrender to take place at the Amole II hotel in Timika. "Now, after I helped them, they betrayed us," Omaleng said. "And my friends thought that I am the one who sold them out to the FBI."

Anton Bahrul Alam, a spokesman for the national police, said, "That's their right to feel deceived. But one thing I know for sure is we have been targeting them for a long time."

Wamang, who the US indictment describes as a separatist rebel commander, acknowledged in a 2004 Australian television documentary that he fired his weapon at the scene. But according to Rumbekwan, Wamang said he believed he was shooting at Indonesian soldiers on a mountain road on Freeport property heavily patrolled by the military. Wamang said he witnessed "retaliation fire" from another group on the ground that he said were Indonesian soldiers.

Under interrogation, Wamang told Indonesian police in a sworn affidavit that he acquired six magazine clips with 180 bullets from security forces, Rumbekwan said. The bullet casings were found on the ground at the ambush scene, Rumbekwan acknowledged.

Human rights activists and others analyzing the case charge that the truth will be harder to determine in the Indonesian court system, where witness intimidation is common and the military wields influence.

S. Eben Kirksey, a US specialist on Papua and a PhD student at the University of California at Santa Cruz, said his research, including interviews with witnesses and participants, indicated that Wamang was set up by Indonesian security forces. "He was there several days prior to the attack, camped out, waiting for information about reported movements of Indonesian troops," Kirksey said.

"Specifically, he indicated to people in conversations prior to going up to the site that he didn't intend to shoot white people, that he was planning to wage war with the Indonesian military."

The detainees were to be moved to Jakarta on Saturday, police said.

In November, the Bush administration, citing national security interests, lifted restrictions on military financing to Indonesia, continuing a process of restoring full military ties. US aid will continue to be guided by progress on human rights, democratic reform and accountability, a State Department spokesman said this month.

[Staff writers Dan Eggen and Dana Priest in Washington and special correspondent Andy Saputra in Jakarta contributed to this report.]