About 250 Boeing employees were working on Air Force One planes with expired security clearance, report says

• Boeing mistakenly allowed workers without the proper security clearance to fly on Air Force One. 
• The company said it alerted the Air Force immediately about the issue and is working to fix it. 
• The Wall Street Journal reported the Pentagon is scrutinizing the issue to see how long it has been ongoing. 

Boeing accidentally allowed employees without the proper security clearance to work on presidential planes like President Biden's Air Force One. 

Roughly 250 workers were reportedly allowed to work on presidential jets, as well as future versions of Air Force One, even after their top security clearances had expired for months, or sometimes even years. 

The error was first reported by the Wall Street Journal but confirmed to Insider. 

A Boeing spokesperson said the company caught its mistake earlier this month and quickly reported it to the Air Force. 

As a result, the Air Force pulled the affected workers off the schedule until their clearances were back up to date. Both the Air Force and Boeing said that as of last Sunday, most employees now have permissions renewed and are allowed back into secured spaces. 

In a statement to Insider, Boeing said no "employee has lost their security clearance nor had it suspended; all the affected employees have a current, valid Top Secret clearance."

The Journal also reported that the Pentagon is probing the security clearance mix-up to discover how long it has been an issue. 

In a statement to Insider, the Air Force said it is "taking the situation very seriously and believes the Boeing Company is making every effort to quickly resolve this issue through their Root Cause/Corrective Action (RCCA) processes." 

This isn't the first stumbling block Boeing has recently encountered in its work with Air Force One. 

In 2018, Boeing struck a deal with then-President Trump to replace some of the company's older jets. Since then, Boeing has said delivery of the new planes will be as much as 3 years behind schedule. The first two new jets were set to begin flying by 2024. 

Boeing's delays have reportedly cost taxpayers $340 million, and the company has reported a nearly $2 billion loss since the plane construction began. 

In a statement, Boeing said that the security clearance hiccup did not cause any more delays in the production of the new jets.