Detailed Instructions: In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.
Q: In this Saturday, Feb. 6, 2016 photo, a SWAT-style vehicle passes along Pearsall Road in Uvalde, Texas. Uvalde County Sheriff Charlie Mendeke said Sunday, Feb. 7, that 19-year-old Dylan Westerburg gunned... (Associated Press) 
  
 McALLEN, Texas (AP) — A 19-year-old killed his mother and two neighbors before turning his gun on himself in a shooting that brought SWAT and various emergency vehicles to a rural area in Texas, authorities said Sunday. 
  
 Uvalde County Sheriff Charlie Mendeke said Dylan Westerburg gunned down his mother Friday afternoon in their home near Uvalde, about 85 miles west of San Antonio. He then went next door and killed two brothers, Arthur and Phinny Norton, Mendeke said. 
  
 Mendeke said investigators haven't determined a clear motive for the shootings. Westerburg lived with his mother in a small cabin about 20 yards from the Nortons' mobile home on the brothers' property. 
  
 Phinny Norton, 60, had some "sort of romantic relationship" with Westerburg's mother, 42-year-old Jennifer Diane Jacques, Mendeke said. Deputies had been called out to the property in the past because of domestic disputes but "nothing violent," Mendeke said. 
  
 Authorities arrived at the scene after a teenage witness called them. The teenage boy was with Arthur Norton, 58, when they saw shotgun shells and broken glass as they approached the Nortons' mobile home, Mendeke said. 
  
 "Mr. Norton enters the house," Mendeke said. "The kid who was with him hears and sees a gun blast and sees Mr. Norton fall to the floor" before running to call authorities. 
  
 When officers arrived they heard another gunshot. Not knowing whether there were multiple gunmen or whether the gunman was dead, authorities surrounded the homes and began evacuating people nearby. 
  
 It was during that search that they found Jacques' body. The family's dog had also been killed. 
  
 Mendeke said he called in about 50 to 60 officers from different agencies as well as a Texas Department of Public Safety SWAT team out of caution. Authorities closed the road leading to the property and they stayed there overnight. 
  
 "I didn't know how many shooters I had in the Norton residence when I found the mother," he said. "You're looking at farm- and ranchland. You could get into a dangerous situation." 
  
 The SWAT team finally entered the Nortons' mobile home on Saturday afternoon and found the Norton brothers and Westerburg dead inside. Mendeke said Westerburg had shot himself in the head. ||||| UVALDE COUNTY, Texas - The names of four people killed in a triple murder-suicide in Uvalde County were released Sunday. 
  
 According to family members and the Uvalde Leader News, killed were Dylan Westerburg, 19; his mother Jennifer Diane Jacqeus, 42; and their neighbors, Arthur Jerome Norton, 58 and Phinny Paul Norton, 60. 
  
 Uvalde County Sheriff Charlie Mendeke said Westerburg shot and killed Jacqeus and then fatally wounded the Nortons. Westerburg shot and killed himself. 
  
 The shootings happened Friday afternoon at a home southeast of Uvalde. 
  
 Uvalde County deputies joined with U.S. Border Patrol agents and Texas Department of Public Safety troopers outside a home for hours following the shootings. 
  
 Lawmen were not sure whether Westerburg was still alive inside, and the heavily armed officers were ready for any trouble. 
  
 Around 1 p.m. Saturday, the officers began leaving the scene, indicating the standoff was over. 
  
 Mendeke said that Westerburg killed himself Friday afternoon. 
  
 Karen Norton Behn told KSAT 12 News, that her older brother, Phinny Paul Norton, was having a romantic relationship with Jacques. 
  
 Behn said that her younger brother contacted police to report concerns about Westerberg. 
  
 "My younger brother called police about a week or 10 days ago and reported that the boy had a gun. I'm ready to go down there first of the week and see what's going on, see it for myself and try to make arrangements for my brothers' funerals." 
  
 Law enforcement officials have not said what the motive of the shootings was. 
  
 Copyright 2016 by KSAT - All rights reserved. ||||| McALLEN, Texas -- Authorities say a Texas teenager killed his mother and two neighbors before killing himself. 
  
 Uvalde County Sheriff Charlie Mendeke said Sunday that 19-year-old Dylan Westerburg gunned down his mother Friday in their home near Uvalde, about 85 miles west of San Antonio. He then went and killed two brothers who lived next door. 
  
 Mendeke says a witness saw Westerburg kill one of the brothers and called for help. When officers arrived they heard a final gunshot that investigators believe was Westerburg shooting himself inside the neighbors' home. 
  
 Authorities surrounded the homes and began evacuating those nearby. Not knowing the gunman was already dead, they weren't able to enter the neighbors' home until Saturday, when they found the three men dead inside. 
  
 The standoff with police ended around 1:30 p.m. Saturday, more than 19 hours after the original call came in, CBS affiliate KENS reported. 
  
 Officials with the Uvalde Fire Department told KENS the standoff was on County Road 369, inside a small mobile home park. 
  
 Mendeke says investigators haven't determined a clear motive. |||||
A:
Police in Texas are trying to figure out what led to three murders, a suicide, and a "standoff" in which a mobile home full of dead people was surrounded by police overnight. Police say that on Friday, 19-year-old Dylan Westerburg killed his mother, Jennifer Diane Jacques, 42, before going next door and shooting two brothers dead, CBS News reports. After a witness called police, up to 60 officers and a Texas Department of Public Safety SWAT team surrounded the brothers' mobile home overnight, the AP reports. The SWAT team finally entered on Saturday afternoon, 19 hours after police were first called, to discover that Westerburg had apparently killed himself as soon as officers arrived. Westerburg and his mother shared a cabin about 20 yards from the mobile home south of the town of Uvalde, which is around 85 miles west of San Antonio. The Uvalde County sheriff says roads were closed and nearby homes evacuated out of caution. "I didn't know how many shooters I had in the Norton residence when I found the mother," he says. "You're looking at farm- and ranchland. You could get into a dangerous situation." The dead brothers have been identified as Arthur Jerome Norton, 58, and Phinny Paul Norton, 60. Their sister, Karen Norton Behn, tells KSAT that Jacques had been having a romantic relationship with Phinny, and Arthur had called police around a week ago because he was worried about Westerburg.