A data leak involving personal details of hundreds of millions of Facebook users is being reviewed by Ireland's Data Protection Commission (DPC).

Axar.az reports that the database is believed to contain a mix of Facebook profile names, phone numbers, locations and other facts about more than 530 million people.

Facebook says the data is "old", from a previously-reported leak in 2019.

But the Irish DPC said it will work with Facebook, to make sure that is the case.

Ireland's regulator is critical to such investigations, as Facebook's European headquarters is in Dublin, making it an important regulator for the EU.

The most recent data dump appears to contain the entire compromised database from the previous leak, which Facebook said it found and fixed more than a year and a half ago.

But the dataset has now been published for free in a hacking forum, making it much more widely available.

It covers 533 million people in 106 countries, according to researchers who have viewed the data. That includes 11 million Facebook users in the UK and more than 30 million Americans.

Not every piece of data is available for every user, but the large scale of the leak has prompted concern from cyber-security experts.