Trump Tower wiretapping allegations
On March 4, 2017, Donald Trump wrote a series of posts on his Twitter account that falsely accused former President Barack Obama's administration of wiretapping his "wires" at Trump Tower late in the 2016 presidential campaign. Trump called for a congressional investigation into the matter, and the Trump administration cited news reports to defend these accusations.
Source: Wikipedia — Trump Tower wiretapping allegations (CC BY-SA 4.0)