Media playback is unsupported on your device Media caption Finger lickin' bad: Faeces found on KFC ice in Birmingham

Bacteria from faeces has been found on ice that was served to an undercover researcher at a KFC restaurant.

The discovery was made by the BBC's Rip Off Britain, which was investigating food hygiene at branches of several big-name takeaways and coffee shops.

A scientist who examined the results told the programme the presence of the bacteria increased the risk of anyone who consumed the ice becoming ill.

KFC said it was extremely disappointed and had launched an investigation.

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Image copyright Google Maps Image caption Faecal bacteria was found from ice served at this KFC in Birmingham

Dr Margarita Gomez Escalada studied the sample, taken from a Birmingham KFC restaurant, at Leeds Beckett University.

She told the programme: "We found high levels of bacteria in the ice.

"The presence of faecal coliform suggests that there's faecal contamination either on the water that made the ice, or the ice itself, and so it increases the risk of getting sick from consuming this ice."

Image caption Dr Margarita Gomez Escalada examined the bacteria samples at Leeds Beckett University

Undercover researchers visited a branch of Costa in Loughborough, the Chicken Cottage in Hampstead, a Café Nero in Bath and the Wimpy in Basildon, as well as the KFC at Martineau Place in Birmingham.

At each location, Rip Off Britain said its researchers asked for a cup of tap water with ice, as this can be an good indicator of standards behind the scenes.

Most of the samples that were taken turned up low and harmless levels of bacteria when tested, Rip Off Britain said.

Dr Escalada said: "It's really hard to say how the faecal bacteria got to the ice that we tested. The thing I think is most likely is that it got there through manipulation. So someone touched the ice and their hands weren't particularly clean."

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Media playback is unsupported on your device Media caption How clean are the UK's restaurants?

Rip Off Britain: Food is broadcast on BBC One at 09:15 BST on weekday mornings from Monday 25 April - catch up on BBC iPlayer

The programme said that the KFC in question had temporarily closed for a deep clean following a zero hygiene rating only weeks before the sample was taken.

Angela Rippon, who co-presents Rip Off Britain said: "When we reported this to KFC they were horrified. They literally leapt to action and they got the Food Standards Agency back.

"This particular place now has a rating of five out five, so they're pretty good."

The presenter said the investigation highlighted the importance of hygiene ratings labels, which restaurants in England have no legal obligation to display.

KFC said it was undertaking "a retraining programme with all team members on our standards for touch point cleaning and procedures".

The restaurant chain added that it took "food safety and hygiene extremely seriously".