A Navajo man accused in the arson-shooting deaths of two tribal police officers pleaded not guilty Friday to new allegations he was involved in the killing near the Utah-Arizona state line.

Ben Atene Jr., 24, who was originally charged last April with two counts of first-degree murder and two weapons violations, now faces two additional allegations of assault with intent to commit murder.Atene appeared before U.S. Magistrate Ronald Boyce for arraignment on the new indictment. Except for pleading "not guilty" to the six charges, Atene was silent during the arraignment.

Utah federal Judge Thomas Greene in August declared a mistrial for Atene because a jury that convicted two other men in the murders failed to reach a unanimous verdict against him.

Jury selection for his retrial is scheduled for Oct. 11. Atene, who is under supervised release at a federal half-way house, contends he was sick at home on the night of the murders, Dec. 4, 1987.