A recent article by Washington Post correspondent Michael Birnbaum revealed that sensitive documents remain loosely secured in the U.S. mission in Benghazi, Libya, weeks after the Sept. 11 attack that killed Ambassador J. Christopher Stevens and three other staffers.

A Libyan military guard stands in front of one of the U.S. mission’s burnt-out buildings during the visit of President Mohammed el-Megarif, not shown, to the U.S. Consulate on Sept. 14, 2012. (Mohammad Hannon/AP)

The documents Birnbaum discovered detail Stevens’ itinerary, emergency evacuation protocols and other information.

The Washington Post’s “The Fold” host Brook Silva-Braga spoke with Birnbaum over the phone about the state of the investigation. Here are some highlights:

How were you able to waltz right into the compound so easily?

I asked the owner of the compound if I could go in, and he said yes.

There’s still no official guard outside the compound ... only two security guards provided by the owner.

One of the things we learned is that the security wasn’t that tight, even when it was an active U.S. installation.

The documents shed new light on how thin that force was — it was a mixture of unarmed private contractors and a Libyan militia based in Benghazi.

It’s become a point of contention as to whether it was a spontaneous attack or a planned attack. One of the documents you uncovered shows there was some concern in the days leading up to the attack.

There is one memorandum from the security office to the militia that was charged with providing security, dated Sept. 9, 2012, just two days before the attack. In these documents, it raises the issue of an attack on the U.S. mission and suggests that security personnel weren’t totally certain that the security presence would be enough in the event of an attack.

Why were these documents still lying around?

The investigation has been moving in­cred­ibly slowly. The FBI has not yet been to Benghazi because of security concerns. I’ve spoken to witnesses who say they haven’t been contacted by either the Libyan or U.S. government.

There are lots of things still in the compound. There are documents that are still there — sensitive things that could endanger peoples’ lives.

Silva-Braga also spoke with former secretary of state Henry Kissinger about the incident:

We have no personnel in Benghazi now, do we? It’s understandable that your reporter could walk in. It’s harder to understand how these documents were left behind. I assume they were left behind because the personnel left in the middle of the attack. It’s surprising no one has gone back. I don’t want to criticize people who were under enormous stress and pressure to evacuate.

Watch the full video here:

Read Birnbaum’s story

See the documents