Shots have been heard at the US Capitol in Washington with reports of streets being cleared around the Government building.
People were cleared from the streets as pictures from the scene show cops swarming close to the Capitol.
One picture shows police officers hunched over something on the ground with more cops rushing to join them.
Twitter user Scott Ferson said: “Cops ran to base of hill. Sounded like three shots fired”.
Filmmakers in a building nearby said they were locked inside a building after hearing gunfire on Capitol Hill.
Twitter user Rolf Wilkin reported seeing lots of heavily armed police after hearing shots fired.