It turns out that the nationwide search for Abid Noraiz Ali, Mustafa Khan Owasi, Iftikhar Khozmai Ali, Adil Pervez, and Akbar Jamal has been called off, because, well, the tip alerting the government that they illegally entered the USA and were up to no good was bogus.
Instead of wondering how many such tips are bogus, I'm comforted by the knowledge, as Amitava Mazumdar has pointed out, that even if they were up to no good, we had little to fear from these five. According to the Ashcroft plan, since they were Pakistani, they would have just registered themselves and we would have found them that way.