NAVAJO, N.M.— Sister Magdalena has returned home _ empty now in the absence of a roommate who had worked so hard to empower people on the Navajo Indian Reservation.

That roommate, Sister Marguerite Bartz, was murdered there on the St. Berard Mission Church property, a killing that has rattled this impoverished reservation town and left parishioners in mourning.

The church property sits along a highway against a scenic backdrop of red rock cliffs near the New Mexico-Arizona border. Her death turned tragedy loose on a town long beset by economic hard times, with its boarded-up, graffiti-scarred houses and weed-strewn playground.

Parishioners sobbed and hugged in the church parking lot as Sister Magdalena returned Wednesday to the residence they shared.

She was in New Jersey when Sister Bartz's body was discovered Sunday. She said she now plans to move to the larger town of Fort Defiance, Ariz., 15 miles south of Navajo.

"She did a lot of counseling with people that were having difficulties," Magdalena said. "It's hard for anybody to understand the depth of what she did. She wanted so much to empower the people. She wanted them to know how good they were."

The FBI is investigating Bartz's death. Spokesman Darrin Jones said Wednesday a quick arrest is not likely but investigators received preliminary autopsy results that showed Bartz "sustained a substantial amount of trauma, likely as a result of a violent confrontation" with her killer or killers.

Jones said agents are withholding the specific cause of death while the investigation continues. However, he said there was no evidence to suggest Bartz was sexually assaulted or that she was targeted because she was a nun or for religious reasons.

A mini-SUV Bartz had used was transported to Albuquerque for processing by investigators. It arrived with a sheet draped over the driver's side, covering the window.

The FBI has declined to provide any motive for Bartz's murder, but said the murder apparently happened Halloween night or early Sunday.