Three years after Annie Jacobsen wrote her article about the terrorist “dry run” she observed on a Northwest Airlines flight, the Department of Homeland Security has released new information that confirms our worst suspicions—not only about terrorist plans for another 9/11, but about DHS’s amazing incompetence, because the incident was not even filed with them until four days later: More details on Flight 327 released.

The inspector general for Homeland Security late Friday released new details of what federal air marshals say was a terrorist dry run aboard Northwest Airlines Flight 327 from Detroit to Los Angeles on June 29, 2004.

Several portions of the report remain redacted. The release stems from a Freedom of Information request by The Washington Times in April 2006. The Times first reported on July 22 that this and other probes and dry runs were occurring on commercial flights since the September 11 terrorist attacks.

Excerpts from 51-page inspector general report:

On the flight, 13 Middle Eastern men behaved in a suspicious manner that aroused the attention and concern of the flight attendants, passengers, air marshals and pilots.

Briefly, the following events occurred. Thirteen Middle Eastern men were traveling together as a musical group, 12 carrying Syrian passports and one, a lawful permanent resident of the United States of Lebanese descent, purchased one-way tickets from Detroit to Los Angeles. Six of the men arrived at the gate together after boarding began, then split up and acted as if they were not acquainted. According to air marshals, the men also appeared sweaty and nervous. An air marshal assigned to Flight 327 observed their behavior and characterized it as “unusual,” but made no further reports at the time.

During the flight, the men again acted suspiciously. Several of the men changed seats, congregated in the aisles, and arose when the fasten seat belt sign was turned on; one passenger moved quickly up the aisle toward the cockpit and, at the last moment, entered the first class lavatory. The passenger remained in the lavatory for about 20 minutes. Several of the men spent excessive time in the lavatories. Another man carried a large McDonald’s restaurant bag into a lavatory and made a thumbs-up signal to another man upon returning to his seat.

Flight attendants notified the air marshals on board of the suspicious activities. In response, an air marshal directed a flight attendant to instruct the cockpit to radio ahead for law-enforcement officials to meet the flight upon arrival. After arriving, Flight 327 was met by federal and local law enforcement officials, who gathered all 13 suspicious passengers, interviewing two of them. An air marshal photocopied the passengers’ passports and visas. The names of the suspicious passengers were run through FBI databases, indicating the musical group’s promoter had been involved in a similar incident in January 2004. No other derogatory information was received, and all 13 of the men were released.

The Homeland Security Operations Center (HSOC) logs show no entries regarding Flight 327 on the day of the flight. Flight 327 was logged into HSOC’s database on July 26, 2004, four days after the events that occurred on the flight were reported by The Times. The suspicious incident was brought to HSOC’s attention by an inquiry from the White House Homeland Security Council.

(Hat tip: LGF readers.)