Police in Texas say they are taking a crash course on the history of fanatical polygamous groups to help solve the murders Monday of four former followers of Ervil LeBaron - the late polygamist and convicted murderer.

Dead after concurrent execution-style attacks at three Texas sites separated by hundreds of miles are Mark Chynoweth, 36; his brother Duane, 31; Duane's daughter, Jennifer, 10; and Eddie Marston, 33.The older Chynoweths and Marston were once accused of committing murders ordered by LeBaron, but they were never convicted. They all reportedly later left LeBaron's Church of the Lamb of God.

LeBaron died in Utah State Prison in 1981 after being convicted of ordering the 1977 murder of polygamist Rulon Allred. But lawmen say he reportedly left a "hit list" containing names of ex-followers he considered traitors. Mark Chynoweth had even reportedly once sought police protection after receiving threats that LeBaron issued from prison.

Two other former LeBaron followers were murdered or disappeared mysteriously in the past year. Dan Jordan was murdered near Manti last October, and Leo P. Evoniuk disappeared from California in May 1987.

Police have said they wanted to talk to two of LeBaron's sons about the Jordan case but couldn't find them - although they were reportedly in Texas somewhere. Police would not comment on whether they are seeking them for questioning in the murders on Monday. "We are seeking four people whose names were given to us by another police agency," said Irving, Texas,

Police Lt. K.L. Rowe.

According to a Houston Police spokesman, Mark Chynoweth was shot in the head about 4 p.m. Monday at Reliance Appliances, a Houston appliance store.

About seven minutes later his brother, Duane, and his daughter, Jennifer, were delivering an appliance in a pickup truck to a vacant home on Rena Street in northwest Houston where they were gunned down.

The street has the same name as a sister of the Chynoweths, Rena. She was one of LeBaron's plural wives, but also apparently later left his church.

"We believe they were set up at the vacant house," the spokesman said.

All the victims were found with shotgun blasts to the head. Duane was found in the driveway. Jennifer was found dead in the truck.

"A witness saw two white men leave in a dark-colored Silverado truck," he said. "We are still trying to talk to the family members. We are looking into the possibility it was religiously motivated."

At 4 p.m., at another vacant house in southwest Irving about 200 miles to the north, Marston was injured with .45-caliber gunshot blasts to the head and chest, according to Sgt. Richard Gilnett, with the Irving Police Department.

Marston, who owned Ed's Appliance in Irving, died at 6:18 p.m. at Parkland Memorial Hospital in Dallas, Gilnett said.

Rowe, with the Irving Police, said, "We are taking a crash course on polygamy. We don't know much about it down here." Police were also questioning reporters at length about what they knew about LeBaron and his followers.

Mark Chynoweth, Rena Chynoweth and Marston were all originally charged with the death of Rulon Allred. All three were found not guilty.

Marston was also charged charged in the 1975 murder of polygamist leader Robert Simons in Carbon County, but was also found not guilty.

The murders on Monday worried other polygamists in Utah who have ties to the LeBaron clan. However, members of other polygamist groups said they feel the violence will likely affect only LeBarons and followers of that group and are not overly worried by it.

Two polygamists who last month were in Colonia LeBaron, Mexico, the home of some LeBaron splinter groups, told the Deseret News that community was already worried that more violence was coming.

They said one of the plural wives of the murdered Dan Jordan was in hiding there because she was afraid of violence.

Also, they said rumors were flying about another hit list containing the names of two of LeBaron's brothers - Ross Wesley, of West Valley City, and Alma, of Colonia LeBaron - plus the name of Fred Collier, a Utah-based polygamist whose priesthood claims apparently are based on the LeBaron's claimed authority.

Ironically, the polygamists said they had not heard any rumors of violence against the Chynoweths and Marston.

Ross Wesley LeBaron told the Deseret News on Monday, "I've been told within the past month that I'm on the top of the list, and that my brother Alma and Fred Collier are on it too. It doesn't scare me too much though; I've been on lists like that before. I have to go on with my life and not worry."

LeBaron added that he feels the only ones who likely need to worry about any violence are those who either claim authority with roots reaching back to his father, Dayer LeBaron, or to Ervil LeBaron himself.

He said also said he feels the spirit of the devil has affected anyone who ever followed any of his brothers, which has "made them crazy and murderers."