The United States Department of Defense spent almost $43 million of taxpayers' money on the construction of a gas station in northern Afghanistan, a figure which is 140 times more than what the structure should have cost, reported the Special Inspector General for Afghanistan Reconstruction.

On top of that, the Pentagon has not been able to explain what made the gas station cost so much.

The Pentagon "charged the American taxpayers $43 million for what is likely to be the world's most expensive gas station," according to SIGAR head John Sopko.

The staggering amount was spent over three years from 2011 to 2014, for what was said to be the construction and then the initial implementation of the gas station. The structure, which was opened back in 2012, was put up to prove that compressed natural gas can be effectively used in vehicles in Afghanistan.

However, the task force that was behind the gas station project ceased operating in March. It is due to this that the Department of Defense is claiming that it does not have the personnel expertise to explain the cost of the structure.

The task force that headed the gas station construction, Task Force for Stability and Business Operations, used to report straight to the Office of the Secretary of Defense, and was a well-funded program to the tune of $800 million.

SIGAR's report found that compressed natural gas filling stations cost only $500,000 to put up in neighboring country Pakistan.

The report added that, even with the addition of security-related costs concerning the gas station's construction and operation, the expenses on the structure's construction appear to be extreme.

"It's an outrageous waste of money that raises suspicions that there is something more there than just stupidity," Sopko said. "There may be fraud. There may be corruption. But I cannot currently find out more about this because of the lack of cooperation."

"Nevertheless, we intend to continue our review of TFBSO activities and specific TFBSO projects, and we intend to fully exercise our statutory authorities to shed light on this $800 million program," SIGAR said in the conclusion of the report.

A spokesman for the Department of Defense said that the Pentagon will continue to provide SIGAR with access to documentation, and offered to help the agency to locate and contact former personnel of the TFBSO.