The child protection charity the NSPCC has said it has been contacted about more than one "vile" Twitter accounts with "disturbing imaged of children."
It has said police are "taking urgent action":
People have expressed concern about a twitter feed with disturbing images of children. We've alerted CEOP. They are looking at it urgently.
Thanks all for raising concerns. We are aware there is more than 1 account. And we will of course be talking to twitter about this.
We share people's concerns about twitter today. Very disturbing. Police taking urgent action. And we will follow up with twitter.
More top news
Greater Manchester Police said "inquiries are ongoing to fully understand the circumstances of the incident."
The US president enjoyed rousing support for his political agenda as a formerly hostile audience cheered his plans in office to the rafters.
The former leader said the party needed to learn lessons after his successor Paul Nuttall failed to unseat Labour in a hard-fought campaign.