SAN FRANCISCO (CBS SF) — Work crews were busy Sunday evening boarding up shops surrounding San Francisco’s Union Square in anticipation for possible violence and vandalism in the wake of this week’s Presidential Election.

While San Francisco police say they don’t have any particular intelligence that violence is planned, shopkeepers were not taking any chances.

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And the situation may be further inflamed by President Donald Trump’s threat to challenge the election results and the peaceful transfer of power.

“I think those are real concerns,” said KPIX 5 political analyst Paul Henderson. “Leaders fighting election results is more reflective of a dictatorship that we see in other countries. And we’ve seen the reversal of those shifts in power translate into military authority and civil unrest. That could happen here as well.”

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“It’s not what we want but cities are preparing to make sure that there citizens are as safe as possible.”

In the past, Henderson said, there have been times when there has been a rocky transfer of power like when Dwight Eisenhower left office and John Kennedy became the elected president.

So in 1963, law was passed detailing just how the process should occur.

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“I think what we are going to see those fights are in the appointment process, the heads of the federal agencies, and in the courts,” Henderson said.