March 23 (Reuters) - The U.S. Department of Defense (DOD) is scrutinizing why Boeing Co employees worked on current and future Air Force One planes without the security credentials required for the highly classified jets, the Wall Street Journal reported on Thursday.

Pentagon officials and Boeing have also been examining for how long the workers lacked current security credentials, the report said, citing an official and a person familiar with the matter.

The report said the security lapse involved about 250 Boeing employees who had access to the jets now in use by the U.S. president and under development in San Antonio.

The U.S. Air Force, DOD and Boeing did not immediately respond to requests for comment.

Boeing notified the Pentagon about the security lapse on March 14, the newspaper said, citing an Air Force spokeswoman.

The company learned of the problem while "conducting a records review of their employees", the spokeswoman told WSJ.

(Reporting by Aishwarya Nair in Bengaluru; Editing by Pooja Desai)