Donald Trump has insisted that his hair is real and not a toupee. "I don't wear a toupee, it's my hair, I swear," the Republican presidential front-runner said of his famous locks at a packed rally in Greenville, South Carolina on Thursday. "But I do use hairspray."

To prove it, he invited an unsuspecting woman from the crowd on stage to check. "Just come on up here," he said. "They are going to let you, you have to do an inspection. This is getting crazy, real quick. We don't want to mess it up too much because I do use hairspray. Is it mine?

"And have I ever met you before? No, but you are very nice, thank you, nice to meet you. Someone has a very nice wife. I don't know who she is, but she is very nice wife. So I am on the front page of The New York Times the first sentence says I wear a toupee, and I don't, I swear to you I don't."

This was Trump's way of hitting back at a New York Times story which reported that a Latino radio show host had dubbed him "El hombre del peluquín, the man of the toupee".

Despite last month's controversial comments on Mexican immigrants causing crime, Trump continued to push for building a major wall at the US-Mexico border. "People are tired of what's happening and part of the plan is a wall," he said.

"Can Trump build a wall?" he asked to cheers. "Someday when I'm not around it'll be called the Trump Wall, and it's gonna be the greatest!"