Clipso Martínez was shot at such close range by a soldier at a protest that his surgeon said he had to remove pieces of the plastic shotgun shell buried in his leg, along with the shards of keys Mr. Martínez had in his pocket, shattered by the blast.
Jorchual Gregory was detained with 10 others who said that over three days they were kicked, pistol whipped, doused with pepper spray and battered with helmets and shotgun butts.
“They wanted to make people afraid so we wouldn’t stay in the streets,” said Mr. Gregory, 19. “But what happened was more protests and more deaths.”
Venezuela has been shaken by more than two months of often violent protests that President Nicolás Maduro says are designed to overthrow him. He has held the opposition responsible for violence that the government says has claimed more than 40 lives, including those of protesters, bystanders and six National Guard soldiers.
Until recently, most countries in the region had either supported Mr. Maduro, said little about the protests or gently urged him toward moderation. But there are growing signs that support for Mr. Maduro in the region is weakening, as some of Venezuela’s neighbors show unease with the government’s response to the crisis, including the aggressive treatment of protesters.
This month, foreign ministers from the Union of South American Nations, a group that Venezuela was instrumental in creating, pressed Mr. Maduro to hold face-to-face talks with opposition parties. With diplomats from Brazil, Colombia and Ecuador sitting in, the government and opposition agreed to create a truth commission to look into allegations of human rights abuses during the protests, which were fueled by frustration with rampant crime, soaring inflation, shortages of basic goods and a government crackdown on dissent.
Adding to the pressure, the former president of Brazil, Luiz Inácio Lula da Silva, voiced unusual public criticism of Mr. Maduro this month, saying that he should “establish a coalition policy” and “lower the tension.”
The comments were particularly noteworthy because Mr. da Silva — a staunch supporter of Mr. Maduro’s mentor and predecessor, Hugo Chávez, who died last year — made a videotaped endorsement for Mr. Maduro when he ran for president last April. Mr. Maduro won the election by a narrow margin.
Michael Shifter, president of the Inter-American Dialogue, a policy group in Washington, said the intervention by other South American countries was prompted by the escalating violence.
“The primary concern is that without any moderation, without any space for dialogue, there was a likelihood of continued crackdown and repression that would spur more violence,” Mr. Shifter said.
The growing concerns in the region coincided with increasing evidence of a pattern of violent behavior by the security forces here. Mr. Maduro has said that “a very small number of security forces personnel” have been “accused of engaging in violence,” and that the government has arrested them. Yet abuse allegations continued to mount, particularly against the National Guard, a military branch at the forefront of the government response to the protests.
Soldiers have been accused of firing shotguns loaded with hard plastic buckshot at point-blank range, injuring numerous demonstrators and killing a 23-year-old woman. Soldiers and police officers have also been widely accused of beating detainees, often severely, with many people saying the security forces then robbed them, stealing cellphones, money and jewelry.
The government — which has faced violent tactics from protesters, including Molotov cocktails — said it is committed to protecting human rights while maintaining order. Last month, Mr. Maduro created a Council of State for Human Rights to investigate wrongdoing. Critics complained that the council included the same government officials responsible for the security forces implicated in abuses: the defense minister and the interior minister.
“There have been police excesses but we are investigating,” the national prosecutor, Luisa Ortega, said in a television interview last month. She defended the National Guard, saying that allegations against it amounted to “a disproportionate attack.”
“If it’s true that there have been excesses by some police personnel, it’s not that the commander of the National Guard gets his people together and tells them, ‘You’re going to go out and violate human rights,’ ” she said.
The Office of the United Nations High Commissioner for Human Rights had voiced concern over reports of security force abuses in Venezuela, and this month the Venezuelan conference of Roman Catholic bishops objected to “the brutal repression of political dissent.”
“The government is wrong to want to resolve the crisis through force,” the bishops said.
Here in Valencia, Venezuela’s third largest city, Geraldín Moreno, a student, was standing outside her apartment complex on Feb. 19, banging a pot in protest, when soldiers rode up on motorcycles, according to her father, Saúl Moreno. She fell trying to run into the complex.
Witnesses said that a soldier got off his motorcycle, pointed his shotgun at her head and fired. The hard plastic buckshot slammed through her eye socket into her brain, her father said. She died after a lengthy surgery on Feb. 22, eight days shy of her 24th birthday.
“The pain will never go away,” Mr. Moreno said. “Every day her absence is greater.”
Mr. Gregory, who said he had been detained with 10 others, had gone to a protest here on Feb. 13 with friends Juan Carrasco, 21, and Jorge León, 25, but when they saw soldiers shooting tear gas and shotguns they ran back to Mr. León’s car. According to the men, soldiers surrounded the car, broke the windows and tossed a tear gas canister inside. Mr. Gregory said that a soldier fired a shotgun at him at close range while he sat in the passenger seat, hitting him in the arms and the back of the head.
The men said they were then pulled from the car and beaten viciously. At one point, Mr. Gregory said, a soldier smashed their hands with the butt of his shotgun, telling them it was punishment for protesters’ throwing rocks. The men said that the soldiers set fire to Mr. León’s car.
They were loaded into a truck with other detainees and driven to a National Guard post. One of the detainees, Oswaldo Torres, 25, a salesman in a brake shop, said that the soldiers pretended he was a soccer ball and kicked him over and over again. The men said they were handcuffed together, threatened with an attack dog, made to crouch for long periods, pepper sprayed and beaten.
Mr. Torres said he was hit so hard on the head with a soldier’s helmet that he heard it crack. “Everything went black,” he said.
The Penal Forum, a legal group, said it had documented 70 cases of alleged abuse so far. “It is continuous and systematic,” said Gonzalo Himiob, a director for the group. “The way they are mistreated is very similar in all parts of the country.”
Interviews with more than two dozen people who said they were mistreated by security forces revealed similar patterns of abuse. In San Antonio de los Altos, outside Caracas, Luis Gutiérrez, 26, said that he and others were cornered in a parking lot on Feb. 19 by soldiers who ordered them to lie down and began kicking them.
Mr. Gutiérrez said one of them kicked him in the face. Surgeons later used screws and metal plates to mend his fractured forehead and broken nose.
“They have the right to detain us because we were blocking the road,” said Mr. Gutiérrez. “But there’s no justification for doing this to us, causing these injuries.”
The prosecutor’s office said it was investigating 145 allegations of abuse and that 17 security officials are in jail. Critics questioned the aggressiveness of the investigations. The number of jailed security personnel had not changed in more than a month. According to the prosecutor’s count last month, only one member of the National Guard, the force that had been most widely accused of abuses, was in jail.
The soldier who fatally shot Ms. Moreno in the face had not been arrested, said Rafael Ramírez, a lawyer for her father. “While it’s true that prosecutors have been receptive to us we have seen a brake” on the progress of the investigation, Mr. Ramírez said.
Like many of the protesters, Mr. Martínez, whose shattered keys pierced his leg when he was shot here on March 20, faced charges of disrupting public order.
“It was easy for them to give me house arrest and say you face so many charges,” he said. “But they never said, ‘We’re going to go find the soldier who shot you.’ ”
Keyla Brito, 41, a housewife in Barquisimeto, said she had been on her way to the butcher shop with her 17-year-old daughter on March 12 when they were swept up by National Guard soldiers, taken with six other women to a military post and handed over to female soldiers.
The soldiers beat them, kicked them and threatened to kill them, according to Ms. Brito, her daughter and two of the other women. Male soldiers threatened to rape them, they said.
Ms. Brito said that a soldier cut off her waist-length hair, leaving it ragged. Her daughter and the other women underwent similar haircuts, they said.
The women said they were released only after being made to sign a paper stating that they had not been mistreated.