As you may have become aware from recent press reports, this is not the first time the Earth has faced an extra-terrestrial threat.
Until now the council had classified this information on a need-to-know basis, but with recent speculation in the media, it has been determined that you now need to know.
The incident, which we have classified "The Bureau" occured during 1962, with the XCOM project's USA precursor project dealing with a major threat.
As you can appreciate, with the event so far in the past, it will take us time to move all documents from the archives and construct simulations of the event for training purposes. We expect to have this process complete this August.
We trust you will use this information wisely.