They have dozens of bone fragments. They have a hatchet. They have a man in jail who claims to have killed seven men and scattered their remains across his rural property.

What investigators don't have yet are names — even the name of the one man Michael Lee Shaver Jr. has been accused of killing so far.

"It sure would be nice to have a victim, but I am confident that we can make this case," Cass County Prosecutor Teresa Hensley said Monday.

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Investigators said they had found about 50 pieces of evidence and searched about 20 percent of the 3-acre lot since Shaver was arrested Friday. The discoveries include dozens of bone fragments, identified by a forensic anthropologist from Kansas State University as belonging to two people.

The search is expected to last several more days.

"We've got a long way to go," Cass County Sheriff's Maj. Jeff Weber said during a news conference Monday. "We will take this as slow as we possibly can."

Shaver, 33, of Drexel, was arraigned Monday on a single count of first-degree murder and one count of armed criminal action. He was being held on $1 million bond.

His mother, Shirley Ann Bryson, who lived with him, was charged with hindering prosecution. That case was not related to the murder charge against her son, and authorities said Monday that she apparently did not know about his alleged crimes.

Weber said scores of law enforcement officers were meticulously sifting through areas that Shaver had indicated would yield clues to the homicides authorities said Shaver told them he committed during drug deals so he could steal their cash and drugs.

Authorities say Shaver told them he would lure the victims — all men between 20 and 40 years old and from the Kansas City area — to his home, shoot them and steal their cash and drugs.

Authorities also said Shaver told them he dismembered the bodies with an ax or hatchet and burned the body parts in a fireplace in his bedroom. After smashing the skull and bones with a hammer, he scattered the ashes and bone fragments in his back yard, authorities said Shaver told them.

Investigators said they believe the deaths began occurring about five years ago, around the time Shaver moved into the house. The most recent remains are only months old, they said.

Deputies arrested Shaver and another man Friday after a failed carjacking.

Shaver told deputies as he was being placed into a patrol car that he knew about human remains on the property where he lived with his mother and that he wanted to talk to someone about it, officials said.