Dr. Frank, maybe, but it has a point. The response would "we shouldn't have let them in in the first place."
Here's a link to a Hindustan Times article--fewer but some different facts. The Pakistanis might be dual nationals or something--well reports are early--and they certainly lived in US and Canada.
Probe progress: 2 Pak nationals held (Hindustan Times
"The Delhi Police have made some headway in its probe into Thursday's attack on the Parliament House complex, with the detention of four people, including two Pakistan nationals. Home Minister L.K. Advani has reportedly given the police a three-day deadline to crack the case.
In a late night swoop, the Delhi Police held the two Pakistani nationals at the Indira Gandhi International Airport just as they were about to leave the country. “We had been following intelligence tip-offs about the movement of suspects and (zeroed in) on these two. They have been identified as Feroz Desani and Safiq Verghy,” said a police officer. One of them was on his way to Atlanta, US, while the other was leaving for Toronto, Canada.
Initial investigations have revealed that they had been staying at the Ambassador Hotel in the Khan Market area for the past fortnight. “We believe that they may have come to India via Nepal and had reached Delhi by train,” added the officer.
..........[more at link]