Witness tells BBC he saw gunman on roof

A man with a rifle could be seen on a rooftop minutes before shots were fired at a Donald Trump rally in Pennsylvania, a witness has told the BBC's Gary O'Donoghue at the scene.

The witness, who called himself Greg, said the man had crawled on top of the building located just outside the event in Butler County.

Read what the witness told the BBC in full here.

https://www.bbc.com/news/videos/c51yly4085lo