Tense stand-offs between protestors pop up across US as country anxiously waits for election results

Pro-Trump protesters, some openly carrying rifles and handguns, gathered outside vote-tabulation centers in a few cities on Friday

Tense stand-offs were developing in pockets around the country between opposing election protesters as America watches anxiously to find out who will be the next president.

Pro-Trump protesters, some openly carrying rifles and handguns, gathered outside vote-tabulation centers in a few cities on Friday, responding to baseless claims by Donald Trump that Democrats were trying to steal the election.

Election officials in several states where Democratic candidate Joe Biden was ahead said the anger outside their doors made them fear for the safety of their employees

Roughly 100 Trump supporters gathered for a third day in front of the elections centre in Phoenix, Arizona, where hundreds of workers were processing and counting ballots.

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“Arrest the poll workers!” the crowd chanted, demanding four more years for Mr Trump. Sheriff’s deputies kept protesters in a “free speech” zone away from the entrance to the building.

Police in riot gear were deployed to the  so-called “stop the steal” rally outside the main government building for the  City of Pittsburgh in Pennsylvania. 

Demonstrators, opposing the president and urging for the vote count to be completed, were also present.

KDKA reporter Amy Wadas reported that the anti-Trump group was chanting, “No Trump, No KKK, No Fascist USA" while at an election warehouse in the city, people gathered for another protest with signs reading “count legal votes.” 

In Detroit, dozens of Trump supporters returned to the streets outside the city’s convention centre, where election workers counted ballots.

“Stop the steal!” the protesters chanted. Some carried signs that read, “Make Elections Fair Again” and “We Love Trump.” 

Police cordoned off streets leading to the building and maintained a close watch on the protest.

The county treasurer in Detroit, Eric Sabree, said he had closed his office because of threats. In a statement, Mr Sabree said the decision was made “in the interest of the safety of taxpayers and our staff” and because of “credible information” from the sheriff’s office.

Evacuations took place in Philadelphia on Friday afternoon after bomb threats were called into an area close to the Convention Center where ballot counting is taking place.

Philadelphia police said that security in the Fashion District mall received two calls from the same individual saying that a bomb was going to go off.

The mall that borders the convention centre was evacuated, The Philadelphia Inquirer reported. Trains in the area were also halted.

K9 units were sweeping the shopping center and said shortly before 3pm that no device had been planted, Philly Voice said.

On Thursday evening, police confirmed that they were investigating an alleged plot to attack the centre where the election ballots are being counted.

A tip came in that an individual or a group was travelling to the city from Virginia in a Hummer with the intention of attacking the election location.

A man was taken into custody and a weapon recovered. It is unclear whether the two incidents are connected.

The eyes of the nation are on Pennsylvania, along with Georgia, Arizona and Nevada, as workers continue to tally thousands of ballots that could decide the presidential election.

AP contributed to this report