The revelation was buried in the US Courts' annual wiretap report, published earlier this week but largely overlooked.
"The federal wiretap with the most intercepts occurred during a narcotics investigation in the Middle District of Pennsylvania and resulted in the interception of 3,292,385 cell phone conversations or messages over 60 days," said the report.
Details of the case remain largely unknown, likely in part because the wiretap order and several motions that have been filed in relation to the case are thought to be under seal.
It's understood to be one of the largest number of calls intercepted by a single wiretap in years, though it's not known the exact number of Americans whose communications were caught up by the order.
http://www.zdnet.com/article/one-federal-wiretap-order-recorded-millions-phone-calls/