Twitter locks millions of accounts after passwords posted for sale

Social network responds to username and password leak by locking affected accounts after spate of hacks targeting Katy Perry, Mark Zuckerberg and NFL

Twitter has been forced to lock millions of users' accounts after 33m purported account details were posted for sale on the dark web.

The details, which were revealed and made available by security site LeakedSource on Wednesday, are thought to be gleaned from other sources, rather than a direct attack on the social network.