Social networking sites MySpace and Tumblr were reportedly breached several years ago but stolen IDs of millions via the attacks were recently put up for sale, reports BBC. The details were leaked only last month when news broke of 167 million LinkedIn account details being available online after a 2012 hack.

It's unclear whether the timing of these leaks were planned or coincidental, according to BBC, and whether there are more to come.

Security researcher Troy Hunt said there must be "some catalyst" behind the releases and adds that millions of IDs from adult dating site Fling have also been put on sale now, although Fling was hacked way back in 2011.

The Tumblr dump is "just a list of emails," according to news site Motherboard, and available at a lower price, while around 360.2 million MySpace accounts are on offer at a higher price. Account status of Tumblr, Fling and LinkedIn can be checked at the data dump on Hunt’s Have I Been Pwned.

Read more details at BBC News.