WASHINGTON - The government has allowed terrorists into America's witness protection program and has failed to provide the names of some of them for the watch list that's used to keep dangerous people off airline flights, the Justice Department's inspector general says.

As a result of the department's failure to share information with the Terrorist Screening Center, some in the witness protection program who were on a "no-fly" list were allowed to travel on commercial flights, the department's watchdog said.

The FBI-managed screening center is the clearinghouse for information about known or suspected terrorists.

In a briefing for reporters Thursday, the Justice Department said it has remedied the problem with a restrictive travel policy that prohibits program participants with no-fly status from traveling on commercial flights. The department declined to say how many people in the program actually flew.

While people involved in terrorism cases have long been eligible for federal witness protection, the Justice Department wouldn't say how many have been in the program. The inspector general's report said it was "a small but significant number."

The Witness Security Program, or WitSec as it is known, protects witnesses from the people and organizations against whom they have testified. The U.S. Marshals Service provides cooperating witnesses with new identities.

The program has been significant in the government's efforts to prosecute terrorists responsible for the 1993 World Trade Center bombing, the 1995 bombing in Oklahoma City, and the 2009 New York subway suicide-bomb plot.

Since the witness protection program began in 1971, it has taken in more than 8,400 witnesses and 9,900 family members and other associates of witnesses. The department said the vast majority of what it referred to as former terrorists in the program were admitted before the 9/11 attacks.

The department said that to date, the FBI has not identified a national security threat tied to the participation of any terrorism-linked witness in the program.

The inspector general's report said that as a result of the department not disclosing information on some known or suspected terrorists, the new, government-provided identities of the witnesses were not included on the consolidated terrorist watch list until the IG noted it.