A 17-year-old student is calling on Michael Gove to help end female genital mutilation in Britain by asking headteachers to train and inform teachers and parents about the horrors of the practice.

Fahma Mohamed is urging the education secretary to write to the leaders of all primary and secondary schools, urging them to flag up the dangers of female genital mutilation (FGM) before the summer holidays, when girls are at the greatest risk. An estimated 66,000 women and girls in the UK have been victims of FGM.

As the face of the Guardian's new campaign to have FGM recognised as a key government priority, Mohamed, one of nine daughters in a Muslim Somali family that came to Britain when she was seven, believes Gove could do more to help curtail the barbaric practice.

She adds her voice to a broad coalition of global charities and campaigners who have joined with the Guardian to urge Gove to act. Supporters can add their names to a petition on the Change.org campaigning website. "If every single headteacher was given the right information, we could reach every single girl who is at risk of FGM," said Fahma, from Bristol. "We could convince these families not to send their daughters abroad and help those girls at risk."

According to government figures more than 20,000 British girls are thought to be at risk of being cut every year but, despite previous government promises to stop FGM, experts have warned that girls are not only still being taken abroad to be cut during the holiday "cutting season", but are also being mutilated in Britain.

Medical groups, trade unions and human rights organisations estimate that there were 66,000 UK victims of FGM in the UK and more than 24,000 girls under the age of 15 were at risk. Victims can be as young as just a few weeks old.

Campaigners have called for better data on how many victims there are in the UK. The government responded on Wednesday night with an announcement that hospitals will begin keeping records of how many of their patients have undergone FGM.

The Guardian spoke to Manika, who was eight years old when she was mutilated in the Gambia. She is now 25 and lives in Scotland. "It really hurt. It's like taking a knife and cutting someone's flesh," she said. After suffering physical complications, she is now terrified of having sex. "I can't let my body move properly so that I can do it. I still have this at the back of my mind … it makes me feel scared."

For her, the consequences are lifelong, and catastrophic. "After I saw the blade, I knew they would definitely hurt me," she said. "This is just like you're taking somebody's life. It's just like you're taking a gun and shooting somebody to death. It's just like it feels for me."

Experts said some families, put off by expensive air travel, were clubbing together to pay for cutters to travel to Britain to mutilate their girls in "cutting parties".

"We have found out that there is a lot of individuals carrying out this process in Scotland and it's becoming quite popular for people from other countries to come here to get the process carried out," said the MSP Margaret McCulloch, of the Holyrood equal opportunities committee.

Reports that "cutters" are at work, some operating out of expensive private clinics, have come from other major cities including London, Birmingham and Bristol, said Sarah McCulloch, from the charity Agency for Culture and Change Management. "Wherever communities [that practise FGM] are residing, it is a problem," she said.

More than 140 million women and girls worldwide have suffered FGM, with up to 98% of girls mutilated in certain African, Middle Eastern and Asian countries. Traditionally seen as a rite of passage carried out to keep girls "pure" before marriage, it is condemned by campaigners as a means of controlling women's fertility and sexual desire.

Despite three decades of legislation against FGM in Britain, there is yet to be a single prosecution. DCS Keith Niven, the Metropolitan police's lead on child abuse, called on members of FGM-practising communities to come forward.

"I need information, I need people to tell me who it is that is committing these crimes," he said.

The lack of prosecutions was a "failure" that has to be addressed, admitted the Home Office minister Norman Baker, speaking before the campaign's launch.

"I'm hopeful we can defeat this in the UK and I think we are making progress. The next 12 months will be important. I'm pretty confident we will get some prosecutions," added Baker, the government lead on FGM. New cases were being "seriously investigated" while some previously closed cases had been reopened, he added.

In France, activists accused Britain of cowardice, arguing that France had come close to eradicating FGM by carrying out controversial physical health checks on children and arresting parents if there was a suspicion that a girl had been mutilated.

Naana Otoo Oyortey, the executive director of Forward UK, which has been central to the FGM debate in Britain and has joined the Guardian's campaign, said it could play a significant role in raising awareness of FGM. "We want the education secretary to come out and say work really needs to be done in school," she said. "Why are we talking about prosecuting parents before we have even sent out information? There has to be a change of heart, and that has to start in schools."

Fahma, who has seen at firsthand among friends and family the devastation that FGM can cause, said that eradicating FGM in a generation was achievable. "We are not going to be quiet. We are not going to shut up. It has taken us this long just to get people talking about it – we don't care how long it takes to make people listen."

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