LAW enforcement agencies can access “eye-watering” amounts of personal information from suspects’ phones using secretive new technology, a data privacy group has warned.

Privacy International said that police forces around the world are increasingly using new tech known as cloud extraction to hack the phones of suspects, witnesses and victims in criminal investigations.

This allows users to obtain information from the cloud, a term widely used to describe data not stored on a user’s device but remotely on a third-party server.

Cloud storage is increasingly being used by apps such as Facebook, Twitter and Instagram, but many app users are unaware of this.

Through these new tools, police forces can obtain far more data than previously, including a recording of person’s voice stored by Amazon’s Alexa virtual assistant, Privacy International warns.

Once officers have a user’s credentials, they can easily and secretly track the person’s online behaviour such as posts, likes, events and connections using their cloud-based accounts, even after they have returned the phone.

Privacy International solicitor Camilla Graham Wood warned that “very little is known” about this new type of technology.

“Cloud extraction technologies give law enforcement the ability to access eye-watering amounts of highly sensitive personal data, not only about individuals but also their friends, colleagues and acquaintances,” she said.

“It is a matter of urgency that law enforcement act with a greater degree of transparency in relation to the new forms of surveillance they are using and that laws which are designed to protect against abuses are updated.”

Israeli surveillance company Cellebrite, which creates mobile phone extraction tools including cloud analytics, admits that it has been working with dozens of police forces in Britain.

Privacy International told the Star that it believes at least one British police force is using cloud extraction.