Hackers who breached U.S. government databases stole personal information of 21.5 million people, officials said Thursday following an investigation into the attack widely blamed on China.

An update from the government's Office of Personnel Management said those affected were 19.7 million who underwent a background investigation, and 1.8 million others, mostly spouses or cohabitants of applicants for government jobs.

They are among the world's most popular websites and are vital diplomatic channels for Iranian officials involved in the nuclear talks. Yet Twitter, Facebook and YouTube remain banned in Iran.

While Foreign Minister Mohammad Javad Zarif leads the way on social media -- his Twitter account has "Verified" blue tick status -- he is far from alone in seeing its benefits.

Brazilian judges have fined Facebook and Google thousands of dollars for failing to remove gruesome photos and videos showing the body of a popular singer killed last month in a car crash.

The fines imposed by a court in Goiana, capital of the central Goias state, are the latest blow in an ongoing tussle over Facebook and Google's policies regarding privacy and publication of offensive material.

The U.S. government's stepping away from a key oversight role of the Internet will strengthen its governance and ease political pressures, the top Internet administrator said Wednesday.

Fadi Chehade, president of the Internet Corporation for Assigned Names and Numbers (ICANN), said the end of the U.S. role is now set for mid-2016, with the transition pushed back by a year to allow time for input from the Internet community and review by the U.S. government and Congress.

A group of computer code experts said Tuesday that law enforcement cannot be given special access to encrypted communications without opening the door to "malicious" actors.

A research report published by the Massachusetts Institute of Technology challenges claims from U.S. and British authorities that such access is the policy response needed to fight crime and terrorism.

Tinder said Tuesday it would verify the profiles of public figures, celebrities and athletes for the smartphone-based dating service.

The fast-growing service, which allows smartphone users to swipe right or left to approve or reject a potential date, also said it makes some 26 million matches each day.

Microsoft has rebranded its subscription-based music services as part of a ramped-up effort to compete with the likes of Apple, Google Spotify and others.

The U.S. tech giant said its Groove Music -- the rechristened name for XBox Music -- will be built into the Windows 10 operating system that is designed to power computers and a variety of mobile devices.

They might be so popular as to be almost an extension of people's arms, but most Americans ditch their smartphones and return to the trusty computer when buying online.

That was the finding of a Gallup survey released Tuesday which said that 74 percent of adults in the United States with smartphones usually turn to their computers for making purchases on the Internet.

FBI Director James Comey called Monday for public debate on the use of encrypted communications, saying Americans may not realize how radical groups and criminals are using the technology.

Comey's comments in a blog post appeared to seek more public support for his view, first expressed last year, that stronger encryption being developed for mobile devices could hurt the efforts of US law enforcement and intelligence operations.

Samsung Electronics Co. forecast a fall in second quarter profit in a sign that sales of its much anticipated Galaxy S6 smartphones failed to meet expectations.

Samsung on Tuesday estimated its second quarter operating profit at 6.9 trillion won ($6.1 billion), down 4 percent from a year earlier. The result represents a 15 percent gain from the previous quarter but it was lower than the 7.23 trillion won forecast in a FactSet survey of analysts.