The people, who were employed by major airlines, airport vendors and other employers, were not identified because TSA is not authorized to receive all terrorism-related information under current inter-agency policies, the report said.

The agency’s “multi-layered process to vet aviation workers for potential links to terrorism was generally effective. In addition to initially vetting every application for new credentials, TSA recurrently vetted aviation workers with access to secured areas of commercial airports every time the Consolidated Terrorist Watchlist was updated,” the report found. “However, our testing showed that TSA did not identify 73 individuals with terrorism-related category codes because TSA is not authorized to receive all terrorism-related information under current interagency watchlisting policy.”