Human Rights Watch and the children's mental health charity, Young Minds, have also confirmed they were affected.

The hack targeted Blackbaud, one of the world's largest providers of education administration, fundraising, and financial management software.

The US-based company's systems were hacked in May.

It has been criticised for not disclosing this externally until July and for having paid the hackers an undisclosed ransom.

In some cases, the data was limited to that of former students, who had been asked to financially support the establishments they had graduated from. But in others it extended to staff, existing students and other supporters.

Read MORE

BBC NEWS