British Information Commissioner's office spent hours overnight in the London offices

Raids have been taking place at the company involved in the Facebook data breach.

Investigators from the British Information Commissioner's office spent several hours overnight inside the offices of Cambridge Analytica in London.

The firm's accused of using the data of millions of Facebook users without their consent.

Silicon Valley journalist Casey Newton says it's the latest of several problems for Facebook.

Both Cambridge Analytica and Facebook deny wrongdoing.