Ellen Nakashima and Alan Sipress, Jakarta – Police are investigating an allegation that Indonesian army special forces carried out the ambush in Papua province last month that killed two Americans and one Indonesian.

The provincial police chief, I. Made Pastika, said today his team was "cross-checking" the story given by a 23-year-old Papua man who claims to have been with the special forces on the morning of August 31 as they set out to ambush teachers working for an international school under contract to Freeport-McMoRan, which is based in Louisiana and owns the world's richest gold and copper mine in Papua.

Separately, the man, who spoke in a telephone interview on condition his name not be published, told The Washington Post that he heard gunfire and said he is "100 percent sure" the shooters were special forces, known as Kopassus.

"He gave a lot of detail, but we are still doing the confirmation, because not all his statements are accurate with what we have found in the field," said Pastika, who was in the capital today to brief the chief of Indonesia's national police force, Da'i Bachtiar, on the high-profile case.

FBI agents are also in Papua to monitor the case, the outcome of which could affect both Freeport's massive operation – it is among the top three taxpayers in Indonesia – and US foreign policy. If the military is linked to the killings, it could severely hamper the Bush administration's quest to restore ties with Indonesia's armed forces, suspended in 1999 to protest the army's role in orchestrating violence in East Timor.

Indonesia's army chief, Gen. Ryamizard Ryacudu, urged prudence today. "Let's just wait until the entire police investigation is completed," he said. "If it is proven that there were army officers involved ... then they will be dismissed and they will be sentenced." Army commanders have blamed the attack on the Free Papua Movement, which has been waging a long-running campaign for independence marked by sporadic violence.

American teachers Edwin L. Burgon of Sunriver, Ore., and Ricky L. Spier of Colorado, and their Indonesian colleague Bambung Riwanto were killed in the attack.

James R. Moffett, Freeport-McMoRan's chief executive officer, visited the Grasberg mine complex Wednesday and told financial analysts in a conference call that mining operations were strong and that the company expected to exceed its previous sales and production estimates for the third quarter. He was also in Jakarta today to meet with Indonesian officials about the case.

Most of the survivors of the attack, which also wounded five people, are back in the United States. They were raked by automatic weapons fire as they rode in two vehicles along a foggy mountain road on Freeport property above a lush rain forest.

In the interview, the Papuan man said that he was ordered by a Kopassus commander to accompany him and nine soldiers on a trip from the town of Timika up the mountain toward the town of Tembagapura, near the mine. He said that along the steep road, he and four special forces soldiers were let out of the vehicle, and the rest continued on. Those who remained behind began drinking "at least five" bottles of whiskey and several bottles of dark beer, he said, adding that he became "totally drunk." Shortly afterward, he said, he heard a soldier's mobile phone ring. It was the commander in the vehicle up the road. "Quickly! Get ready!" he said he overheard the commander order.

"Then suddenly I heard a very, very strange noise, like bang! Followed by a gun shooting – didditditdit didditditdit. It sounded very close." When the shooting was over, he said, the vehicle returned, driven by a special forces officer. The commander "told us to rush, get into the car and leave the place right away," he said.

Edmund F. McWilliams Jr., a former US Embassy political counselor here and an independent human rights activist, said that an admission of drunkenness should not lead analysts to dismiss the man's story out of hand. The Indonesian military in general, he said, "would often use drugs or alcohol to get people in a pliable mood, to counter the possibility of any resistance at the last minute to what they want them to do."

Pastika said he found discrepancies in the man's account: His team found no bottles near the site; the bullet cartridges found at the site did not match the type of rifle the man said the soldiers were carrying; and the man said that he was the only Papuan in the group that went up the mountain, although some of the survivors told police that there was more than one Papuan, who generally have dark complexions and Melanesian features.

Still, Pastika stressed that he is not ruling anything out, including the possibility that the man was brought along by Kopassus with the intention of using him as a possible fall guy.

"He said he was so frightened for his life that he came forward," Pastika said. The man is under police protection in Jayapura, the provincial capital of Papua, which sits at the far eastern end of the Indonesian archipelago.

Pastika has said he is investigating whether the military carried out the attack in an effort to wrest more money and concessions from Freeport or other multinational companies for which it provides lucrative security services.

In the interview, the man said he served for 11 years in Tenaga Bantuan Operasi, a local militia trained by Kopassus, and had taken part in several of its operations in Papua. Human rights activists in Papua who have also interviewed the man said they found his story credible.