During the 2020 protests in Portland, Or the US Marshalls flew a plane equipped cell phone snooping equipment over downtown for hours every day. The equipment acts as a mock cell tower so mobile phone traffic in the area gets routed through their tools before going to an actual tower. It also collects data from wifi in the area, in addition to whatever unknown abilities it has. This was around the time anonymous federal agents were picking up people off the streets in white vans and hiding in bushes shooting pepperballs at people walking by.