Donald Trump has again courted controversy during a US Republican party presidential candidate debate.

He said he would bring back the waterboarding interrogation technique and "a hell of a lot worse".

He also told his rival Jeb Bush to be quiet during a heated exchange over government seizures of private property, adding, "he wants to be a tough guy, and it doesn't work very well".

The debate which got off to an awkward start when Ben Carson missed his introduction cue, was also a tough for Marco Rubio who clearly struggled as his rivals attacked his "inexperience".