A poster campaign aimed at mothers and carers who suspect a girl is at risk of female genital mutilation is being rolled out across major cities in England and Wales.

The posters urge women, particularly those in Somali, Kenyan and Nigerian communities which have a higher prevalence of FGM, to call an NSPCC-dedicated helpline if they are suspicious. The posters will be placed in washrooms, and also sent to schools, GPs’ surgeries, police stations and hospitals to be displayed in staff areas.

More than 20,000 girls under the age of 15 could be at high risk of FGM in England and Wales each year, with nearly 66,000 women having experienced the procedure.

Announcing the poster campaign, the home secretary, Theresa May, said: “FGM is illegal and it is child abuse. The government is absolutely committed to tackling and preventing this harmful practice in order to safeguard and protect all girl and women who may be at a risk. It often results in severe consequences for their physical and mental health and we must do everything we can to eradicate it for good.