RUSSELLVILLE, ARK., DEC. 31 -- Law enforcement authorities said today they believe Ronald Gene Simmons Sr. may have been driven to a murderous rage after learning that his wife was secretly hoping to divorce him.

Pope County sheriff's investigators said that the 47-year-old former Air Force sergeant's anger about Rebecca Simmons' divorce preparations is their best guess of what prompted the mass slayings that left her and 15 others dead.

"If our information about a possible divorce is true, that would be a strong motive," said Lt. Jay Winters, one of the investigators.

The speculation about such a motive came as citizens in this small, western Arkansas city mourned Simmons' two former coworkers, who were gunned down during a 30-minute shooting rampage before he was arrested Monday.

Kathleen Cribbens Kendrick, a 24-year-old secretary who coworkers said rebuffed Simmons' romantic advances, was buried this morning.

Hundreds attended a funeral for Kendrick, who was a divorced mother of a young son and described as an "attractive, popular" person who retained a sunny disposition even during difficult periods in her life.

A fire truck served as the hearse at the afternoon burial of J.D. Chaffin, a firefighter who police said was gunned down by Simmons while working at a part-time job. Chaffin, 33, was the father of three children.

"He liked having a solid, secure job," Russellville Fire Chief Earl Price said of Chaffin. "He was friendly . . . well-liked in the community."

Simmons evidently harbored ill will not toward Chaffin but toward his employer, Taylor Oil Co., according to investigators. Taylor once owned the convenience store where Simmons worked until he quit earlier this month.

Funerals also were held for Simmons' daughter, Sheila McNulty, 24; her husband, Dennis, 33, and their children, Sylvia, 6, and Michael, 21 months. Also Simmons' son, William Simmons, 23; his wife, Renata, 21, and their son William, 20 months.

Pope County Sheriff Jim Bolin said today that autopsies of the bodies of the 14 Simmons family members revealed that the younger children had been strangled and that the older victims had been shot at least once in the head. Simmons' wife, Becky, 46, was shot twice in the head, and daughter-in-law Renata Simmons was shot five times in the head and twice in the neck, Bolin said.

Loretta Simmons, one of 14 slain family members found at the family's home in the Ozark foothills 15 miles north of here, discussed her parents' troubled marriage with some high school friends, according to 17-year-old Karen Warnick.

"Her mom was saving up money to get a divorce," Warnick said Loretta Simmons told her.

During the summer, Warnick said Loretta Simmons sent her letters because the Simmons family had no phone and Loretta Simmons' father refused to let her leave the property.

"I could tell you I'm doing OK but I'd be lying," Loretta Simmons wrote Warnick last July. "I haven't left the house or seen anyone since school was out! Oh, I would if I could, but . . . . "

Elsewhere in the letter, which was written in capital letters, she wrote: "My Dad hates me, says I'm not good enough yet. He claims I'm conceited, & you can't talk to my mom about anything. She doesn't understand. Who else is there? . . . God. But it seems I can't get close to Him. I used to pray to Him when I was little, when my parents would fight but it wouldn't help."

Investigators said they do not know how Simmons learned of his wife's divorce plans, but they said they believe she was trying to keep him from finding out.

"From everything we've learned about the family and his behavior, we think he would have been the last person she would have told," Winters said.

Earlier this week, officials in New Mexico, where Simmons previously lived, said that in 1981 Simmons had been charged with incest. The charges were brought after one of his daughters said she was carrying her father's child, former state prosecutor Steven Sanders said.

When a grand jury returned an indictment, the family fled to Arkansas, officials said.

Simmons was being held today at a state mental hospital in Little Rock.

He has been charged with two counts of murder and four counts of attempted murder from Monday's shooting rampage. Winters said investigators are waiting until all evidence is collected and examined before bringing charges on the family murders.