BeatBullying has backed calls from the NSPCC for social media sites to do more to protect their young users.
BeatBullying founder Emma-Jane Cross said:
"This research underlines the urgent need for social networking sites to take their young users' safety much more seriously.
"We believe in the right of children to go online without fear of being bullied or harassed, and this cannot be achieved until social networks put adequate resources behind safeguarding and user verification policies."
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The latest on Shamima Begum makes headlines.
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Ministers will seek an order ‘depriving’ the 19-year-old Londoner of her British citizenship, her family’s solicitor said.