Disagreement over timing of arrests

NBC reports NBC News has learned that U.S. and British authorities had a significant disagreement over when to move in on the suspects in the alleged plot to bring down trans-Atlantic airliners bound for the United States.

They were two days away from a trial run, and what might they have done if in the trial run they had been discovered? Would they have activated the explosive right there? And the real event was scheduled for August 16. That is not that far away.

A senior British official knowledgeable about the case said British police were planning to continue to run surveillance for at least another week to try to obtain more evidence, while American officials pressured them to arrest the suspects sooner. The official spoke on condition of anonymity due to the sensitivity of the case.