Nick Clegg welcomed police action over Twitter abuse after a man was arrested on suspicion of harassment after threats were aimed at a feminist campaigner on the social networking site.
It comes after Caroline Criado Perez faced a deluge of threats on Twitter over the course of more than a day after she successfully campaigned for a woman's picture to be put on a new bank note.
The Deputy Prime Minister said: "What is unacceptable offline is unacceptable online."
He added that he had "probably" received lots of abuse on Twitter.
More top news
A list of commemorative events as the UK marks a decade to the day 52 were killed and hundreds injured in London terror attacks.
Larger stores could be allowed to open beyond the current six-hour limit on Sundays under a relaxation of rules in Wednesday's Budget.
IS is now attracting women and whole families as well as young men - but will any return to carry out another 7/7?