The Lincoln County Sheriff’s Office is investigating its fourth murder in as many months.

A man found dead in the lower Yaak River area in Lincoln County, originally  investigated as a suicide, now is believed to have been murdered, according to Sheriff Roby Bowe.

The 69-year-old victim was found in his minivan by a person driving up a gravel U.S. Forest Service road, who then reported it to police. In an updated press release Tuesday, Bowe reported that the man died of “apparent blunt force trauma.”

Bowe declined to give any further details about the case.

The victim’s name has not yet been released while the Sheriff’s Office attempts to locate and notify family members.

“We’re having a very difficult time locating family right now,” Bowe said. “They’re outside of the state, numbers are wrong, people are deceased. It’s been tough.”

The first of the four recent Lincoln County homicides occurred on Dec. 8, 2011, when Kristina Lynn Welch, 52, was arrested for the shooting death of Charles Welch, 52.

Less than a month later, Dale Kinniburgh Jr., 51, killed himself after reporting to police that he had just murdered his wife, Catherine Kinniburgh, 55, on Jan. 3.

Then, on Jan. 6, James Bonifas, 75, was arrested for the shooting death of his daughter, Suzanne Campbell, 41, after reporting to police that she had died during the night.

Charges have been filed in both the Dec. 8, 2011, and Jan. 6 cases.

“It’s been a tough start to the new year for us,” Bowe said. “It’s keeping everyone busy.”