Tensions over the still undecided U.S. presidential election are prompting some state and local officials to increase security for those charged with counting the remaining votes.

Supporters of Republican President Donald Trump and Democratic challenger Joe Biden have increasingly focused their attention on states like Arizona, Nevada and Pennsylvania, where slim margins have made calling the race nearly impossible.

And the tensions have grown as allegations of irregularities in the vote-counting process have sparked protests outside buildings where the tally is going on.

"I am concerned for the safety of my staff," said Joe Gloria, registrar of voters in Clark County, Nevada, on November 5, after about 75 people, some wearing Trump T-shirts, chanted "Stop the Steal" and protested outside the county's election center the night before.

There were no reports of violence, but following scares at other locations across the country, Gloria said his office was not taking any chances.

"We're putting measures into place to make sure that we have the security that's necessary," he said. "We have law enforcement who are protecting us."

In the neighboring state of Arizona, election officials in Maricopa County announced Thursday they would be setting up a "free speech zone" for protesters with the help of the local sheriff's office.

"It is imperative that we balance the protection and well-being of our election workers and volunteers with the constitutional right of protesters," the Maricopa County Elections Department said in a statement, adding the changes would allow staff to count votes and leave the building "without the threat of intimidation."

Maricopa County officials made the move following a protest by about 200 Trump supporters, some armed with rifles or handguns, outside the Election Department in Phoenix on November 4.

The county called on armed law enforcement officers to escort election department staff from the building.

Confrontations between protesters and election officials were also reported November 4 in Detroit, Michigan, when police officers barred Trump and Biden supporters from a convention center where votes were being counted.

Officials said windows were covered up to prevent protesters and onlookers from taking video of the poll workers and volunteers.

Overnight protests November 4 in Portland, Oregon, also turned violent, with police making 10 arrests and seizing multiple firearms as well as ammunition.

Back in Michigan, the state's attorney general complained November 5 on Twitter about harassing phone calls and threats to her staff.

"The safety and security of election officials and election workers is paramount," a spokesperson for the National Association of State Election Directors told VOA in a statement November 5.

"Election officials have contingency plans in place," the spokesperson added.

Federal and state officials have been bracing for potential violence for months, anticipating frayed nerves due to a close election combined with the likelihood that results would be delayed because of the high number of mail-in ballots.

State security and election officials working to get ahead of a combination of factors threatening to spark chaos around the Nov. 3 vote

"Election result delays and recounts could result in protests and attempts to occupy election offices," the New Jersey Department of Homeland Security and Preparedness warned in a threat assessment issued in late September.

Law enforcement officials, including officials at the FBI, also expressed concern before the election that U.S. adversaries, such as Russia, Iran and China, could use the days after the November 3 vote to spark "upheaval and discord," which could lead to violence.

"Our preparations for [the 2020 election] take into account the current climate of the country," an FBI official told VOA at the time. (VOA)

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