Donald Trump said he was not warned about shooter Thomas Matthew Crooks by the Secret Service, despite reports from rally-goers an hour before he got on stage.

The Republican presidential candidate told Fox News host Jesse Watters: “Nobody mentioned it. Nobody said it was a problem.

“[They] could've said, "Let's wait for 15, 20 minutes, 5 minutes.

“Nobody said…I think that was a mistake.”

Trump later questioned how Crooks made it onto the roof at the Butler rally last Saturday (13 July).

Trump said: “How did somebody get on that roof? And why wasn't he reported, because people saw he was on that roof.”

The full interview airs on Fox News on Monday (22 July).