Tension is rising ahead of the elections in the U.S.: Heavy metal barriers, 3 meters high, have been placed around the presidential residence.

According to USA Today, heavy metal barriers three meters high have been placed around the presidential residence. The Naval Observatory, where Vice President and Democratic candidate Kamala Harris resides, as well as other important buildings in Washington DC, have also been similarly secured.

Metropolitan Police Chief Pamela Smith stated in a press conference on the eve of the election, "We will never tolerate violence in our city. We will not allow damage to property or behaviors that threaten public safety and the electoral process."

The measures taken by the Secret Service remind us of the events of January 6, 2021, when supporters of then-President Donald Trump stormed the Capitol in an attempt to prevent Congress from certifying Joe Biden's election victory.

As Harris and Trump are neck and neck in the polls, and experts are assessing the election as "uncertain," tensions have reached their highest levels in recent history.

Washington Mayor Muriel Bowser expressed her sadness at a press conference on Monday, stating, "Clearly, I am very upset that the situation has come to this point. However, the way to deal with anxiety is to work and be as prepared as possible."

Workers have also boarded up the windows of some shops and buildings on Pennsylvania Avenue near the White House with wooden panels.

In the days leading up to the election, reports indicated that ballot boxes were set on fire and fights broke out between voters and officials at polling centers.

Here are the latest predictions from three key experts following the elections:

'The Nostradamus of Presidential Elections'

Historian Allan Lichtman, known as 'Nostradamus' for correctly predicting 9 out of the last 10 US elections, insists on his prediction made at the beginning of September.

Using a model based on true-false questions representing the 13 keys to the White House, rather than polls and commentators, the American University professor shows Harris as the winner.

Based on the ruling Democratic Party, Lichtman identified only three negative keys for Harris: midterm gains, the advantage of the incumbent president, and the charisma of the current president.

Lichtman emphasized that his prediction has not changed and will not change in the face of any "October surprise" or other events that may occur before the election.

On Saturday, Lichtman noted that FiveThirtyEight and Predictit showed the election as a tie, while The Economist indicated Harris was ahead by 52%.

On X (formerly Twitter), he wrote, "Other models that long predicted Trump would win have finally begun to align with the Keys to the White House model."