CARACAS, Venezuela — The death toll has risen to 61 following fierce gunbattles between inmates and National Guard troops at a Venezuelan prison, a hospital director said Saturday. About 120 more people were wounded in one of the deadliest prison riots in the nation’s history.

Penitentiary Service Minister Iris Varela said Saturday that officials had begun evacuating inmates from the Uribana prison in Barquisimeto and transferring them to other facilities, but she did not provide an official death toll.

However, Dr. Ruy Medina, director of Central Hospital in the city of Barquisimeto, told The Associated Press that the number of dead had risen to 61. He initially told Venezuelan news media after the Friday uprising that about 50 were killed.

Medina said that nearly all of the injuries were from gunshots and that 45 of the estimated 120 people who were wounded remained hospitalized. Some underwent surgeries for their wounds.

Relatives wept outside the prison during the violence, and cried at the morgue Saturday as they waited to identify bodies.

The riot was the latest in a series of deadly clashes in Venezuela’s overcrowded and often anarchical prisons, where inmates typically obtain weapons and drugs with the help of corrupt guards. Critics called it proof that the government is failing to get a grip on a worsening national crisis in its penitentiaries.

The gunbattles seized attention amid uncertainty about President Hugo Chavez’s future, while he remained in Cuba recovering and undergoing treatment more than six weeks after his latest cancer surgery.

Government officials pledged a thorough investigation, while some critics said there should have been ways for the authorities to prevent such bloodshed.

Nayibe Mendez, the mother of a 22-year-old inmate in the prison, told the AP that she was able to talk by phone with her son and he was uninjured.

“What they say is that there were shots all over the place, and they don’t know where they came from,” Mendez said. “It was a massacre. A full list hasn’t come out of the dead and injured.”

Mendez spoke by telephone from the morgue, where she said she went out of solidarity. “We’re all hurt. No matter what, a prisoner has a right to live,” she said, demanding that the authorities fully investigate what happened.

Varela said during a news conference that officials decided to evacuate all inmates from the prison in order to “close this chapter of violence.” She said victims had wounds from guns, explosives and knives or other sharp weapons made by the inmates.

Varela did not provide any estimates of the numbers killed and injured, and instead criticized Venezuelan news media at length for their coverage of the violence.

Vice President Nicolas Maduro called the bloodshed tragic and said Prosecutor General Luisa Ortega Diaz and National Assembly President Diosdado Cabello would lead the investigation.

“The prisons have to be governed by law,” Maduro said on television early Saturday.

The riot was the deadliest in nearly two decades. In 1994, more than 100 inmates died in the country’s bloodiest prison on record, at a prison in the western city of Maracaibo. In 1994, about 60 inmates were killed in a riot in a Caracas prison.

Varela said that the violence erupted on Friday when groups of inmates attacked National Guard troops who were attempting to carry out an inspection. She said the government decided to send troops to search the prison after reports of clashes between groups of inmates during the past two days.

Douglas Briceno said his nephew, an inmate, was wounded in the foot during the shooting. “I think he’s out of danger,” Briceno told the AP.  “I haven’t been able to communicate with him because they don’t let me pass to the prison.”

Opposition leader Henrique Capriles condemned the government’s handling of what he and many other critics call a growing crisis in the country’s prisons.

“Our country’s prisons are an example of the incapacity of this government and its leaders. They never solved the problem,” Capriles said on his Twitter account. “How many more deaths do there have to be in the prisons for the government to acknowledge its failure and make changes?”

Venezuela currently has 33 prisons built to hold about 12,000 inmates, but officials have said the prisons’ population is about 47,000.

The Venezuelan Prisons Observatory, a watchdog group, said in a statement that in 2007 the Costa Rica-based Inter-American Court of Human Rights had ordered the government to seize weapons that inmates had in their possession at Uribana prison and to take measures to avoid deaths in the facility. The group called for the government to release a list with the names of the dead and wounded in Friday’s violence, as well as details about weapons seized in the search.

“No one doubts that inspections are necessary procedures to guarantee prison conditions in line with international standards, but they can’t be carried out with the warlike attitude as (authorities) have done it,” said Humberto Prado, an activist who leads the prison watchdog group.

“It’s clear that the inspection wasn’t coordinated or put into practice as it should have been. It was evidently a disproportionate use of force,” Prado told the AP.

His group says Uribana prison was built to hold up to 850 inmates but currently has about 1,400.

Similar though less deadly clashes have flared repeatedly during the past few years.

In April and May, a prison uprising in La Planta prison in Caracas blocked authorities from going inside for nearly three weeks. One prisoner was killed and five people were wounded, including two National Guard soldiers and three inmates.

Two months later, another riot broke out at a penitentiary in Merida, and the Venezuelan Prisons Observatory reported 30 killed.

In August, 25 people were killed and 43 wounded when two groups of inmates fought a gunbattle inside Yare I prison south of Caracas.

Chavez’s government previously pledged improvements to the prison system, but opponents and activists say the government hasn’t made progress.

Varela, the prisons minister, said news media including Globovision and a local newspaper had run reports on the inspection by authorities, which she said had in fact been a “trigger for the violence.”

Prado denied that, saying: “The problem isn’t the work of the media. The problem is that the government hasn’t disarmed the prison population.”