China-linked hackers appear to have gained access to sensitive background information submitted by U.S. intelligence and military personnel for security clearances that could potentially expose them to blackmail, the Associated Press reported on Friday. In a report citing several U.S. officials, the news agency said data on nearly all of the millions of U.S. security-clearance holders, including the Central Intelligence Agency, National Security Agency and military special operations personnel, were potentially exposed in the attack on the Office of Personnel Management. It said more than 2.9 million people had been investigated for a security clearance as of October 2014.

By Yasmeen Abutaleb SAN FRANCISCO (Reuters) – Twitter Inc Chief Executive Officer Dick Costolo abruptly announced he was stepping down on Thursday amid increasing scrutiny of the company's slow user growth and inability to attract advertisers at the same rate as its competitors. Costolo will be replaced by co-founder Jack Dorsey on an interim basis. According to a source familiar with the matter, it was Costolo's decision to leave, and Costolo said he brought it up with the board last year as it began talking about succession planning.

(Reuters) – The attorneys general of New York and Connecticut are investigating Apple Inc's negotiations with music companies to look for signs of potential antitrust violations. The attorneys general want to know whether music labels colluded or were pressured into favoring Apple's paid music subscription service, which was released on Monday. Apple launched Apple Music on Monday, a $9.99-a-month streaming music service that will likely alter the dynamics of how consumers listen to music as the music industry grapples with declines in downloaded songs and tries to figure out new ways to get people to pay for music.

By Richard Cowan WASHINGTON (Reuters) – Top U.S. tech companies are warning the Obama administration against imposing new policies that the companies say would weaken increasingly sophisticated encryption systems designed to protect consumers' privacy. In a strongly worded letter to President Barack Obama on Monday, two industry associations representing major software and hardware companies said, “We are opposed to any policy actions or measures that would undermine encryption as an available and effective tool.” The Information Technology Industry Council and the Software and Information Industry Association, representing tech giants, including Apple Inc, Google Inc, Facebook Inc, IBM and Microsoft Corp, fired the latest salvo in what could be a long fight over government access into smart phones and other digital devices.

By Andrea Shalal WASHINGTON (Reuters) – A massive breach of U.S. federal computer networks disclosed this week is the latest in a flood of attacks by suspected Chinese hackers aimed at grabbing personal data, industrial secrets and weapons plans from government and private computers. The Obama administration on Thursday disclosed the breach of computer systems at the Office of Personnel Management and said the records of up to 4 million current and former federal employees may have been compromised. U.S. officials have said on condition of anonymity they believe the hackers are based in China, but Washington has not publicly blamed Beijing at a time when tensions are high over Chinese territorial claims in the South China Sea.

By Andrea Shalal and Matt Spetalnick WASHINGTON (Reuters) – Data stolen from U.S. government computers by suspected Chinese hackers included security clearance information and background checks dating back three decades, U.S. officials said on Friday, underlining the scope of one of the largest known cyber attacks on federal networks. Accusations by U.S. government sources of a Chinese role in the cyber attack, including possible state sponsorship, could further strain ties between Washington and Beijing.

Alibaba Pictures Group Ltd , the film and entertainment unit of China's largest ecommerce company, said on Thursday it plans to raise $1.6 billion in a share offering to select investors to finance media-related acquisitions. Alibaba Pictures plans to sell 4.2 billion shares at HK$2.90 each, putting the total deal at HK$12.18 billion ($1.57 billion), according to a Hong Kong stock exchange filing. Alibaba Pictures, previously known as ChinaVision Media Group, is flush with cash after raising nearly 5 billion yuan ($807 million) in 2014 from a massive share offering that put Alibaba in control of the company.

By Foo Yun Chee BRUSSELS (Reuters) – U.S. tech firm Disconnect has filed a complaint to EU antitrust regulators against Google's ban on its privacy app, accusing the Silicon Valley giant of abusing its dominant market position. Disconnect, set up four years ago by former Google engineers, says its app protects users of the Android operating system from invisible tracking and malware distributed through advertisements. It said Google had abused its position by blocking the app from the Google Play store last year, and had gained an unfair advantage over competitors by integrating its own privacy and security services into its own products.

By Patricia Zengerle and Warren Strobel WASHINGTON (Reuters) – The legal authority for U.S. spy agencies' collection of Americans' phone records and other data expired at midnight on Sunday after the Senate failed to pass legislation extending their powers. After debate pitting Americans' distrust of intrusive government against fears of terrorist attacks, the Senate voted to advance reform legislation that would replace the bulk phone records program revealed two years ago by former National Security Agency contractor Edward Snowden. Although the Senate did not act in time to keep the program from expiring, the vote was at least a partial victory for Democratic President Barack Obama, who had pushed for the reform measure as a compromise addressing privacy concerns while preserving a tool to help protect the country from attack.