Washington, D.C. ? The FBI has been slow to update the national terror suspect watchlist — and the lapses pose real risks to U.S. security, a Justice Department audit has found.

A report by the Justice Department’s Inspector General, Glenn Fine, found that 12 terror suspects who were either not watchlisted or were slow to be added to the list may have traveled into or out of the United States during the period when they were not placed on the list.

Auditors also found significant delays in taking people off the list once they were no longer considered suspects.

The watchlist, which is used to screen people entering the U.S. and by local law enforcement, contains more than 1.1 million names.

Of those names, nearly 24,000 were based on outdated information or nonterrorism case designations, auditors concluded.