As many as 280,000 teenage girls are suffering from sexual abuse because they believe it is an accepted part of relationships or do not believe they can stop it, the NSPCC has warned.

In a disturbing report, the charity said fewer than 20 per cent of cases are reported by young people, as opposed to the majority of cases in which adults are abused. "Many girls are being forced to carry out sexual acts and in some cases are even being raped," said Jon Brown of the NSPCC. "We're not talking about 'horse play' or teenagers experimenting, this is often serious abuse. But unfortunately many of the girls don't see it that way. They think it's just part of a relationship they have with a boy or may be too embarrassed or frightened to tell anyone about it."