President Donald Trump's campaign has racked up over one million dollars in outstanding bills from at least 12 American cities, according to an estimate from the Center for Public Integrity.

Most of the totals have typically come from police-related costs, such as providing security and overtime pay for officers.

Albuquerque was the latest city to bill the Trump campaign for security services and municipal facility use provided for the rally, totaling $211,000.

Municipal billing for campaign rallies vary from city to city, and most don't sign contracts ahead of time, meaning there is no binding agreement mandating payment.

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President Donald Trump's campaign has racked up over one million dollars in outstanding bills from at least 12 American cities, according to an estimate from the Center for Public Integrity.

Most of the totals have typically come from police-related costs, such as providing security and overtime pay for officers.

The Washington Post reported the amount and it was confirmed to them by the Center for Public Integrity, a nonprofit news organization.

Some of the cities that the Trump campaign has outstanding invoices from include:

El Paso, Texas: $569,000 for a February rally

Minneapolis, Minnesota: $530,000 for an October 10 rally

Albuquerque, New Mexico: $211,000 for an October rally

Tucson, Arizona: $82,000 for a March 2016 rally

Spokane, Washington: $65,000 for a May 2016 rally

Albuquerque was the latest city to bill the Trump campaign for security services and municipal facility use provided for the rally. On Thursday, the Hill reported the city had sent the campaign an invoice totaling $211,175.94.

"The President's campaign stop in the Albuquerque area cost the taxpayers hundreds of thousands of dollars, including over 1500 hours of police overtime that was required by the campaign," Albuquerque mayor Tim Keller said in a statement to the Hill.

"We are asking the Trump campaign to pay our taxpayers back for the costs from his campaign stop," Keller said.

Ahead of the Minneapolis rally earlier this month, Trump and his campaign assailed its mayor when the city attempted to get paid in advance for hosting the event. The campaign team called the $530,000 total "a phony and outrageous bill for security, the Minneapolis Star Tribune reported.

Municipal billing for campaign rallies vary from city to city, and most don't sign contracts ahead of time, meaning there is no binding agreement mandating payment. The Secret Service — the law enforcement agency that usually requests security — has previously asserted there is no funding mechanism to compensate city governments for costs incurred.

Other local governments with heftier budgets have been able to absorb the bill, and some even have policies barring governments from billing politicians for security costs.