A paternity test is not usually something done on a whim. But rather than go to a clinic or appear on daytime television, one enterprising businessman is hoping to persuade people to give a swab of their DNA at the side of the road.

Driving the streets of New York in his brightly coloured van with the words "Who's Your Daddy?" emblazoned on the side, Jared Rosenthal is on the lookout for men who doubt that they are the father of their child. "They flag us down, they pull us over and they talk to us," he told CBS News.

The tests cost around £200-£300 and the results are available in a couple of days. Mr Rosenthal said most of his customers are men with a child in tow. But the service is also used by women who want to prove to a reluctant father that a child is theirs.