According to BBC News – the US share-trading app Robinhood has been hit by a security breach that has exposed the names or email addresses of more than seven million people.

The company says the breach affected "a limited amount of personal information for a portion of our customers". And it does not believe the most sensitive information it gathers - US social security numbers and financial information - was revealed.

Robinhood said it had rejected a demand for payment and reported the attack. Instead of complying with what it called "extortion", Robinhood said it had notified law-enforcement authorities and hired an external cyber-security firm to help deal with the incident.