Robert Hannigan is shown in Manila, Philippines, in 2008. He became chief of the British eavesdropping agency Monday.

Story highlights

New chief of UK spying agency says big tech firms must cooperate in fight against terror

GCHQ director Robert Hannigan says ISIS is skilled in the use of social media platforms

They "have become the command-and-control networks of choice for terrorists," he says

In the Financial Times, Hannigan says intelligence agencies face a huge challenge

London CNN  — 

UK spy chief Robert Hannigan called on big U.S. tech companies to do more to help governments combat terrorism Tuesday, as he described social media as “a terrorist’s command-and-control network of choice.”

In an opinion piece written for Britain’s Financial Times newspaper, Hannigan, the new director of UK government eavesdropping agency GCHQ, said there must be greater cooperation from the private sector to tackle the threat.

His comments play into the continuing debate over the conflict between people’s right to privacy online and governments’ need to ensure national security, intensified by the revelations last year of former NSA contractor Edward Snowden over mass government surveillance programs.

In a rare public statement, Hannigan accused U.S. tech companies of being in denial over terrorists’ use of the Internet.

“They are exploiting the power of the web to create a jihadi threat with near-global reach. The challenge to governments and their intelligence agencies is huge – and it can only be met with greater co-operation from technology companies,” he said.

The extremists use such platforms as Twitter, Facebook and WhatsApp to reach their target audience in a language they understand, Hannigan said.

Their methods include making use of popular hashtags for other stories in the news, such as Ebola or the World Cup, to disseminate their message, he said. They create slick videos and have learned that showing the full extent of their brutality turns people off, he said – hence their posting of videos of beheadings that stop short of showing the moment of death.

Information requests

Google, WhatsApp, Facebook and Microsoft have not yet responded to a CNN request for comment on the spy chief’s call for more cooperation.

A public policy communications officer for Twitter, Nu Wexler, said the company was not able to break out how many of the requests for information made to it by governments relate to terrorism, but he said Twitter is suing the U.S. government for the ability to do so.

In the six months that ended on June 30, Twitter received 78 account information requests from the UK government, its Transparency Report shows. Some information was produced in 46% of those cases.

Over the same period, 61% of all worldwide requests for account information received originated from the United States, with 1,257 requests in total. Some information was produced in nearly three-quarters of cases.

‘Noisy channel’ for radicalization

Hannigan, who took the reins as GCHQ director on Monday, said that ISIS militants show an alarming ease with new media that presents a new challenge for authorities.

“Terrorists have long made use of the internet. But ISIS’s approach is different in two important areas,” he said.

“Where al-Qaeda and its affiliates saw the internet as a place to disseminate material anonymously or meet in ‘dark spaces,’ ISIS has embraced the web as a noisy channel in which to promote itself, intimidate people, and radicalise new recruits.”

If Britain’s intelligence and security agencies are to combat this effort, private sector firms – including the largest U.S. technology companies that dominate the Web – must do more to facilitate lawful investigations, he said.

“I understand why they have an uneasy relationship with governments. They aspire to be neutral conduits of data and to sit outside or above politics,” he said.

But, he said, “However much they may dislike it, they have become the command-and-control networks of choice for terrorists and criminals, who find their services as transformational as the rest of us.”

The new generation of extremists is also helped by the additional encryption measures now widely available to users of the Internet and smartphones, Hannigan said.

“These are supplemented by freely available programs and apps adding extra layers of security, many of them proudly advertising that they are ‘Snowden approved,’ ” he wrote.

“There is no doubt that young foreign fighters have learnt and benefited from the leaks of the past two years.”

Recent efforts by Google and Apple to encrypt their latest smartphones in ways that would prevent law enforcement from accessing certain private data have alarmed the U.S. Federal Bureau of Investigation.

FBI Director James Comey told reporters in recent weeks that he was “very concerned” that the companies were “marketing something expressly to allow people to place themselves above the law.”

‘Lost insight’

A former top U.S. intelligence official also told CNN last month that ripping the cover off secret U.S. surveillance programs had pushed foreign terrorists underground and out of intelligence services’ reach.

“We’ve lost collection against some individuals, people that we were concerned about we are no longer collecting their communications,” said Matt Olsen, who until September led the National Counterterrorism Center. “We lost insight into what they were doing.”

Snowden, whose massive leaks on intelligence-gathering programs resulted in espionage charges from the U.S. government, has been living in Russia for the past year.

In an interview in May, he said he had no choice other than leaking the highly classified information, since he believed the Constitution was being violated.

CNN’s Lindsay Isaac and Kevin Liptak contributed to this report.