The fast food chain told Fortune its 177,000 employees across the U.K. deserve to work in a “safe, respectful and inclusive workplace”, but added in light of the claims it had “clearly” fallen short.

The U.K. arm of the brand—which employs nearly two million people worldwide—signed an agreement in February with the Equalities and Human Rights Commission pledging a zero-tolerance approach to any form of harassment.

The legally binding agreement saw McDonald’s agree to roll out anti-harassment training for staff as well as support for restaurant managers to help them prevent sexual harassment on their sites.

But the employees—some of whom were as young as 17—say their complaints to senior members of staff about sexual assault, racism and harassment went ignored.

The investigation conducted by the BBC discovered 31 allegations related to sexual assault, 78 related to sexual harassment, as well as 18 allegations of racism and six allegations of homophobia.

Among the testimonies was a 17-year-old member of staff based in Cheshire, north-west England, who said a colleague 20 years senior exposed himself to her, used a racial slur and said he wanted to make a “black and white baby” with her.

Another former employee said she was 17 when a senior manager choked her and grabbed her bottom while working in Plymouth, south-east England, while a 16-year-old male employee working in Hampshire, south England, was reportedly offered vapes by a manager in return for sexual acts.

Alistair Macrow, CEO of McDonald’s U.K. & Ireland said the company will investigate the allegations, adding: “All proven breaches of our code of conduct will be met with the most severe measures we can legally impose, up to and including dismissal.”

‘Toxic work environment’

An employee named Shelby told the BBC her resignation letter to McDonald’s explicitly told managers the company had a “toxic” work environment.

Shelby, who didn’t share her surname, began working at a McDonald’s restaurant in Berkshire, west of London, when she was 16. She says she was “warned” by managers to stay away from a particular employee in his 50s.

Older male members of staff would wait for younger female colleagues to walk past them in the cramped conditions of the kitchen, Shelby said, in order to grope them as they walked by.

On one occasion last summer, Shelby says the member of staff she had been warned about grabbed her and pushed her onto his groin.

“I just froze,” she said. “I felt disgusted.”

Shelby said she raised the issue with a senior member of management but no action was taken.

McDonald’s told the BBC it was “deeply sorry” to hear about what Shelby went through.

‘Abhorrent and unacceptable’

U.K. & Ireland CEO Macrow told Fortune that more than 2,000 McDonald’s managers had completed the awareness training, but allegations claim complaints were frequently ignored.

A former employee who worked in Birmingham, central England, said she quit after she was smacked on the bottom by a male colleague when she was 19. The incident was caught on camera and she says she was left with a bruise.

Despite reporting the incident to her manager with video evidence, the staffer says she had to keep working with the man and therefore quit as a result.

17-year-old Chinyere, who worked in a McDonald’s in Cheshire, said she was racially and sexually harassed by an older man, but was told to get back to work by an employee responsible for staff wellbeing when the incident was raised.

Chinyere, who didn’t give her surname to the BBC, said her stepfather wrote to the franchise, head office and the police about the harassment—at which point the man was fired.

McDonald’s told the BBC it had apologized unreservedly to Chinyere, describing her case as “abhorrent and unacceptable.”

It added: “It takes a great deal of courage to speak up and as soon as we were made aware of the situation the individual in question was offered both internal and independent external support.”