However, the picture authorities were working from had been fleshed out substantially since the intelligence from Afghanistan arrived Wednesday.

Authorities now believe, like several self-radicalized American jihadists before them, that the Sept. 11 anniversary plotters journey to jihad began in the U.S., took them to the Afghanistan-Pakistan region in July and had them, according to the CIA informant whose information is the hard bottom of the case, return to the U.S. on Aug. 31 or Sept. 1 to carry out an anniversary bomb plot…

The pool of names was culled from hundreds men who flew into the U.S. from south Asia in August. That list was developed by running names through all terror watchlists and intelligence files available to the U.S. government.

In sifting and narrowing the names, authorities also used a formula that included the ages of potential cell members — the informant said they would be in their 30s or 40s — date of travel, and multiple travel routes to and from the Afghan-Pakistan region.