William Mitchell Hudson arrived to help seven campers and later returned to kill them, according to an arrest affidavit in the case.
On Tuesday, family spokesperson Steven Woodruff identified the victims as Carl Johnson, 77, and his daughter, Hannah Johnson, 40; her 6-year-old son, Kade; and Mrs. Johnson's boyfriend Thomas Kamp, 46; and Kamp's two adult sons from a previous marriage, Nathan and Austin Kamp, of California.
The only survivor was identified as Cynthia Johnson, Carl's wife. She sustained minor injuries.
Anderson County has not officially released the list of victims pending completion of the autopsies.
The incident occurred Saturday and Sunday along County Road 2217 about 12 miles northwest of Palestine off of U.S. Highway 287 in a rural community of Tennessee Colony.
In the affidavit, according to Cynthia Johnson, Hudson, 33, arrived in the camp Saturday on an orange tractor and helped the family pull a vehicle from the mud.
Later, he returned and had a drink with the group before accompanying several of the campers into the surrounding woods. Cynthia Johnson then heard several gunshots.
Hudson then emerged from the woods alone and chased Carl Johnson and Hannah Johnson into a camper trailer.
The affidavit said Cynthia Johnson heard two gunshots and saw her husband fall on the steps of the camper. She ran and hid and heard several more gunshots. She stayed in hiding until she felt it was safe to move, the affidavit said.
According to Anderson County Sheriff Greg Taylor, the survivor used a cellphone to call 9-1-1 around 7 a.m. Sunday. Deputies found Mrs. Johnson along the side of CR2217, which fronted the properties.
Deputies arrived in the 800 block of County Road 2217 about 12 miles northwest of Palestine off of U.S. Highway 287 and discovered Johnson and his daughter dead in a camper trailer.
Investigators from the sheriff's office, the Anderson County District Attorney's Office, Texas Rangers and Palestine Police Department investigated the crime scene and began searching for the four missing campers.
The affidavit notes investigators canvassed the area at a home in the 1100 block of CR2217 and located a red tractor with visible blood stains. Investigators saw Hudson through a glass door with what they believed to be blood stains on him.
Hudson was located Sunday afternoon at his mother's home, also located along CR2217, and was taken into custody without incident.
The bodies of Kamp, his two sons, and Hannah Johnson's son were found in a pond behind Hudson's home at 1:15 p.m. Monday. Taylor said evidence suggested the bodies were placed and submerged in the pond.
The Franklin Sun Journal reported that Carl and Cynthia Johnson were employees of the University of Maine at Farmington and retired to Texas and eventually settled in Anderson County. Hannah moved to Texas to be closer to them.
Kamp had lived for several years in Midlothian with Ms. Johnson and her son.
In August, Kamp purchased the 15 acres where the family was camping. Kamp's property adjoined land owned by the Hudson family, according to the Anderson County Appraisal District.
The land where the incident occurred is rural and transitions from open fields to wooded areas with uneven terrain and creeks throughout.
Woodruff said the weekend camping trip was to end Sunday.
On Tuesday, Taylor said investigators expected to continue gathering evidence at the crime scene that spans 50-75 acres for at least two more days. Hudson was arrested and charged with one count of murder in the deaths and is being held on a $2.5 million bond. Additional charges against Hudson are expected, Taylor said.
Hudson had recently been arrested for assault within the last few weeks, Taylor said.