As Donald Trump prepares for a rally in Louisiana ahead of the state’s gubernatorial election, the president is reportedly on the hook for hundreds of thousands of dollars in local security costs in at least six other cities where his campaign has held rallies and events.

This week, the campaign threatened to sue over its unpaid $530,000 security bill in Minneapolis, according to CNN. The arena that hosted the event has withdrawn its request, but the city maintains that the cost of services provided for campaign events should come from Mr Trump’s campaign chest and not city coffers.

Minneapolis mayor Jacob Frey said that the city’s taxpayers “should not have to bear the brunt of operating costs resulting from the president’s visit”.

It’s the latest in a series of unpaid invoices, some as much as three years old, well before Mr Trump was elected president in 2016.

In June, the Center for Public Integrity reported Mr Trump owed more than $840,000 from invoices across the US, not including the latest bill from Minneapolis. CNN found that six of those cities still are waiting for checks.

Minneapolis protesters clash with police outside Trump rally Show all 12 1 /12 Minneapolis protesters clash with police outside Trump rally Minneapolis protesters clash with police outside Trump rally IMAGES INCLUDE EXPLICIT LANGUAGE: Counter protesters confront horse-mounted law enforcement after a rally by U.S. President Donald Trump in Minneapolis, Minnesota. Reuters Minneapolis protesters clash with police outside Trump rally Anti-Trump protesters hold signs outside the Target Center in Minneapolis, Minnesota, ahead of a "Keep America Great" rally AFP/Getty Minneapolis protesters clash with police outside Trump rally A counter protester holds a sign before a rally by U.S. President Donald Trump in Minneapolis Reuters Minneapolis protesters clash with police outside Trump rally The state is home to some of the President’s most prominent critics – including senator Amy Klobuchar and congresswoman Ilhan Omar AFP/Getty Minneapolis protesters clash with police outside Trump rally Both the president’s backers and his detractors were, for the most part, kept separate EPA Minneapolis protesters clash with police outside Trump rally On the fringes of the action the president’s supporters clashed with protestors AP Minneapolis protesters clash with police outside Trump rally A protester with a whistle attempts to interrupt U.S. President Donald Trump while he spoke Getty Minneapolis protesters clash with police outside Trump rally Minneapolis Police create a blockade to hold back protestors Getty Minneapolis protesters clash with police outside Trump rally On the arrival of the police protestors could be seen jeering and hurling projectiles at officers AP Minneapolis protesters clash with police outside Trump rally Officers deployed pepper spray during the protests AP Minneapolis protesters clash with police outside Trump rally Baby Trump balloons are carried by a counter protester before the rally Reuters Minneapolis protesters clash with police outside Trump rally Anti-Trump protesters hold signs outside the Target Center in Minneapolis, Minnesota AFP/Getty

Mr Trump’s largest invoice came from El Paso, where a February rally cost $470,417.

Among Mr Trump’s outstanding bills were a $65,124 tab from Spokane, Washington in May 2016 and a $47,398 bill from a rally in Eau Claire, Wisconsin in April 2016, both several months before the election.

While in office, Mr Trump racked up unpaid bills in Mesa, Arizona; Lebanon, Ohio; and Burlington, Vermont, for a total of $89,122.

CNN found that four other cities in the Centre for Public Integrity’s report did not have any owed balances.

It’s difficult to determine who actually is liable for the cost of police and security to accommodate the large crowds and traffic for Mr Trump and his motorcade. There rarely are contracts or agreements between the campaign and municipal governments, which ultimately determine whether to dispatch the additional services, despite Secret Service details requiring them.

Protesters burn MAGA hats outside Donald Trump rally in Minneapolis

A representative from one city told CNN that the city does not typically bill for city services provided to campaign events. Another city representative said they do send invoices but they also don’t expect they’ll actually be paid.

The Centre for Public Integrity argues that the Trump campaign could be flouting federal campaign finance laws for failing to address it debts owed to local governments. Law states that political committees “shall report a disputed debt … if the creditor has provided something of value to the political committee”.