A magic ceremony was held on the Navajo Reservation to thwart a federal investigation of the killing of two tribal lawmen, a witness told an FBI agent.

Special Agent Timothy J. Healy testified Monday afternoon that when he interviewed witness Julius Crank, "He said there was a ceremony to block the investigation and that it was very strong, and it caused one of the medicine men to die."This testimony was just one of the many bizarre aspects of the murder case unfolding in a 13-hour hearing Monday. Some defense witnesses, Navajo Indians who supposedly knew about the killings, took the stand to recant earlier statements to investigators or the grand jury, saying the FBI coerced false testimony.

But others said the FBI's version is correct, and the agents themselves testified they did not make unfair threats or promises and were not abusive. Two admitted they raised their voices during questioning, and one said he had used an obscenity.

U.S. District Judge J. Thomas Greene adjourned the session after 9 p.m. Monday, saying he would have a decision on Tuesday. Participants sweltered during the last several hours of the hearing after the courthouse's air conditioning was turned off.

"It's like one big sauna," Greene said of the heat.

The jury selection process was set for Tuesday afternoon, with the actual trial not expected to begin until Thursday.

Thomas Cly, Marques Atene, Vinton Bedonie and Ben Atene are charged with killing the officers, Roy Lee Stanley and Andy Begay, on Dec. 4, 1987. In Monday's hearing, defense lawyers tried to have the indictment dismissed because of alleged government misconduct.

Phillip Bosely Jr. testified that he was intimidated in questioning when handcuffs were laid on him by a Bureau of Indian Affairs officer, Oliver James Seamans.

He was given a polygraph test and told he failed it. He wanted to call a lawyer, but a Navajo officer told him "if I did I would go to jail with him (the lawyer) also," Bosely said.

He gave a false statement under this pressure, then wanted to recant, he said. But FBI agent Timothy Healy "told us that if we changed this again we're going to jail, and this is where he took us." Healy drove Bosely and another witness to the Salt Lake City-County Jail, and then away from the jail, he said.

So next day, when he testified before the grand jury, he gave an untrue statement, he said. The truth is "I wasn't there" at the bonfire when the lawmen were killed, he said.

But Seamans denied the handcuff incident and Healy, who was present for some of the questioning, said he never saw it either.

Healy explained the trip to the jail by saying he showed two witnesses the sights in Salt Lake City, including the LDS Temple, the Federal Building, the marshal's office and the jail.

Healy said it is true that when a witness failed a polygraph test he was told he had failed, and Healy admitted he used an obscenity and shouted.