Facebook has started offering users the option of securing their messages with end-to-end encryption. This new service will allow the social networking giant’s more than a billion account holders, including jihadist and terrorist groups, to message one another below the radar of law enforcement surveillance, reports The Washington Times.

Facebook's Secret Conversation Worries Officials

Encrypted messaging for the masses

Announcing the feature, the company explained in a blog post, “That means the messages are intended just for you and the other person — not anyone else, including us.”

In a statement, Facebook said the Secret Conversation feature was slated to be deployed to select users on Friday, followed by a wider rollout later this summer. The social networking giant, by implementing end-to-end encryption, aims to give its users a way of communicating over the proprietary Messenger application in a manner that no one can decipher the correspondence between the recipient and the sender. This feature is alarming for law enforcement officials.

A previously released communication protocol called Signal is used for the secret conversation function. Signal is free and open-source software and can be used by anyone. Signal has been implemented by other messaging platforms, including Google Allo, WhatsApp, and an eponymous encryption app released in 2014.

Facebook inherited a popular messaging service upon acquiring WhatsApp messenger in 2014 for roughly $19 billion. In April, WhatsApp deployed end-to-end encryption to its users, and now, with Facebook joining, the two could provide a good share of the connected world with the option of communicating in secrecy.

John Hopkins computer scientist and cryptologist Matthew D told Wired magazine in an interview, “This is just a huge number. It brings access to encrypted messaging to nearly a billion more people.”

Issues facing Facebook

Law enforcement agencies have been against end-to-end encryption, especially after the San Bernardino terrorist attack in December. The digital security measures used by the slain shooter prevented authorities from easily accessing his iPhone.

Recently, after Facebook failed to aid authorities in deciphering communications related to an international narcotics investigation sent over WhatsApp, the Brazilian government froze $6 million in funds belonging to the social media giant.

Along with the opposition, Facebook will also have to overcome technological limitations. The technology that allows end-to-end encryption is compelling the company to offer its Secret Conversation feature through its Messenger app only, and the functionality is limited to just one device, which means messages encrypted and sent using a smartphone will not be legible to its writer if viewed from a web browser or any platform other than the same mobile device.