LA VICTORIA, Venezuela -- The young soldier staggered back to his post and fell to his knees, crying hysterically as a comrade took his gun. The bodies of eight unarmed people -- including two children -- were later found burned, gagged and shot at a ranch down the road.
Neighbor Maria Caicedo witnessed the scene and said she has felt betrayed and afraid ever since.
"You think you're being protected by someone, and look at what happens," she said.
The massacre last month near Venezuela's lawless border with Colombia has deepened public mistrust of the Venezuelan military, soon after it deployed thousands of additional troops along the border to keep out Colombia's leftist rebels, right-wing paramilitary fighters and drug traffickers.
Top Venezuelan defense officials condemned the slayings, blamed on a soldier in a murderous rage who was swiftly arrested. The results of a confidential investigation conducted by civilian prosecutors have so far been shown only to victims' relatives. One relative, speaking on condition of anonymity because the results were not supposed to be released, said they indicate rape was the motive and that the soldier acted alone.
Still, the killings have made it more difficult for the soldiers to assert their authority. Resentment boils, seen in graffiti such as "Get out, army murderers!" and a protest shortly after the massacre that drew nearly 1,000 people.
Some residents say the Venezuelan soldiers can be abusive and ineffective at times, conducting random interrogations for hours, stripping people of documents, even robbing homes and firing at people for minor infractions. In one military operation that went awry last year, a 14-year-old boy was riddled with bullets after soldiers mistook him for a guerrilla.
Venezuelan Attorney General Isaias Rodriguez said the detained soldier, Luis Jefferson Lira Rodriguez, 20, admitted involvement in the July 20 massacre at Ranch Adi but said he acted on orders from at least one other lieutenant who claimed there was a Colombian rebel camp nearby.
For some residents, doubts remain about how the single soldier managed to keep eight people under control.
But the relative who spoke on condition of anonymity said a survivor -- a 9-year-old boy who later died in a hospital from severe burns -- told authorities the soldier arrived alone at the house and was let inside by his mother, Flor Maria Lizarazo, who recognized the serviceman from a nearby military checkpoint.
The soldier was angered after his overtures toward Lizarazo were rejected, the relative said. Using his assault rifle to take a hostage, he ordered everyone to lie on the floor while Lizarazo's husband was forced to tie them up.
The relative said investigators discovered the soldier had a criminal history, including the rape of a 12-year-old girl and illegal drug use, and tested positive for cocaine and marijuana at a military hospital after his arrest.
Although neighbors describe the area around the ranch as relatively trouble-free, the Colombian rebel stronghold of Arauca is just across the river. Colombia's two largest guerrilla groups often cross over, extorting money from farmers and ranchers, and carrying out assassinations, residents say.
Venezuelan President Hugo Chavez and Colombian President Alvaro Uribe have tried to cooperate more to improve border security. In June, Venezuela said it sent up to 6,000 more troops to the border region, joining about 15,000 soldiers working to secure the 1,370-mile frontier of mountains and dense jungle.
There nonetheless were at least 30 assassinations in the first three months of the year around El Nula, a Venezuelan parish of 12,000 people near the ranch, said Rev. Acacio Belandria, a Jesuit priest.
Caicedo and her family moved next door to the ranch last year after fleeing violence in Tame, Colombia. She wonders if they are any safer, and says her two young daughters now hide under the bed whenever soldiers approach the house.
"We came hoping to find more tranquility," she said. "We didn't know that our worst enemy was right behind our backs."