Figures obtained by the NSPCC show more than 8,000 under-18s were accused of sexual offences against other children in the last two years.
The children's charity contacted 42 police forces across England and Wales with a Freedom of Information request asking for the number of under-18s who had been accused, the youngest victim and the youngest accused. Of the police forces contacted, four did not respond.
The youngest child to be accused was aged just six, while the youngest victim had not yet reached their first birthday.
More top news
Questions on Russia and Syria are sure to dominate Defence Secretary Michael Fallon's meeting with his US counterpart Ash Carter.
Smoking could kill two million Chinese in 2030 with the country facing a "growing epidemic of premature death from tobacco".
A great-great-great-grandmother has become an unlikely star at the age of 93 after her grandson shared a video of her dancing to rap music.