SACABA, Bolivia - Bolivia's interim president met with a U.N. envoy to discuss the country's crisis Saturday, a day after security forces fired on supporters of former President Evo Morales in a clash that killed eight people and raised fears that violence could escalate.

On leaving the meeting with interim leader Jeanine Anez, U.N. envoy Jean Arnault said the United Nations is concerned about the violence in Bolivia and hopes it can contribute to an accelerated pacification process leading to elections.

U.N. human rights chief Michelle Bachelet issued a statement earlier in the day calling the deaths “an extremely dangerous development.”

“I am really concerned that the situation in Bolivia could spin out of control if the authorities do not handle it sensitively and in accordance with international norms,” she said.

Protesters said police fired Friday when demonstrators tried to cross a military checkpoint in Sacaba, a town near Cochabamba. Many of the protesters were coca leaf growers loyal to Morales, who had been Bolivia's first indigenous president before being pressured to step down by Bolivia's military chief after weeks of widespread protests over a disputed election.

Witnesses to the clash described seeing the bodies of several protesters and dozens of people rushed to hospitals, many covered in blood.

Presidency Minister Jerjes Justiniano told reporters that five people were killed and an estimated 22 injured. He accused protesters of using “military weapons.”

On Saturday, Bolivia's national Ombudsman's Office raised the death toll to eight.

Police and soldiers broke up fresh blockades of flaming logs and tractors Saturday on the road linking Sacaba to Cochabamba, but there were no immediate reports of deaths.

Fears of escalating violence were stoked when angry demonstrators and relatives of the victims gathered at the site of the shootings late Friday chanting, “Civil war, now!”

Morales, who was granted asylum in Mexico after his Nov. 10 resignation, said on Twitter that a “massacre” had occurred and he described the interim government led by Anez as a dictatorship.

At least 13 other people died during the earlier unrest that preceded Morales' departure, according to the Ombudsman's Office. Several came in clashes between the president's backers and those who accused him of using vote fraud to win the Oct. 20 presidential election.

On Friday, Anez said Morales would face possible legal charges for election fraud if he returned home from Mexico City. She also has said Morales would not be allowed to participate in a new presidential election, which is supposed to be held within three months.

The ousted leader, meanwhile, contended this week that he is still president since the country's legislature has not yet approved his resignation.

Morales stepped down following nationwide protests over suspected vote-rigging in an Oct. 20 election, which he claimed to have won to gain a fourth term in office. Morales has denied there was fraud, though an Organization of American States audit reported widespread irregularities.

Families of the victims held a candlelight vigil in Sacaba. A tearful woman put her hand on a wooden casket surrounded by flowers and asked: “Is this what you call democracy? Killing us like nothing?”

The Inter-American Commission on Human Rights condemned what it called “the disproportionate use of police and military force” in the clash.

“Firearms must be excluded from the operations used to control the social protests,” the commission said on Twitter along with a video that showed the five people lying dead on a blanket. Soldiers and police in riot gear had been patrolling the area with armoured vehicles in the previous days.

“We're not going to let them make us flee, nor humiliate us. Let me say to Mrs. Anez that she must denounce this. If not the whole country is going to close in on her,” said Enrique Mamani, a local resident. “They have carried out a state coup, paid off the military, paid off the police. There's political persecution against our leaders.”

Backers of the interim government deny there was any coup against Morales, saying police and the military withdrew backing from him only to avoid shedding civilian blood during the mass protests against him.

Supporters of Morales, who was Bolivia's president for almost 14 years and was the last survivor from the “pink tide” of South American leftist leaders, have been staging disruptive protests since his resignation, setting up blockades that forced closure of schools and caused shortages of gasoline in the capital.

Anez, who had been the highest-ranking opposition official in the Senate, proclaimed herself president after Morales resigned, saying every person in the line of succession ahead of her - all of them Morales backers - had resigned.

The constitutional Court issued a statement backing her claim that she didn't need to be confirmed by Congress, a body controlled by Morales' Movement Toward Socialism party.

Much of the opposition to Morales sprang from his refusal to accept a referendum that upheld term limits that barred him from seeking another term. He got the courts to declare the limits a violation of his human rights to seek office.

Associated Press Writers Carlos Valdez and Paola Flores in La Paz contributed to this report.