Battle lines were being drawn Wednesday over a US federal judge's order that Apple help the FBI crack the encryption on an iPhone linked to the San Bernardino, California, terror attack.

Apple chief executive Tim Cook refused the judge's order in an open letter posted on the company's website Tuesday shortly after Judge Sheri Pym ordered the company to help the FBI access data they believe is stored on the phone.

The December 2 attack in San Bernardino was carried out by Syed Rizwan Farook and his wife, Tashfeen Malik, at a holiday party at the county office where Farook worked. Fourteen people were killed.

Police killed Farook and Malik later that same day in a shoot-out.

The FBI wants Apple to help it hack into Farook's iPhone by building a new version of the iOS software that would circumvent security features and install the software on the iPhone, which was recovered during the investigation.

The White House Wednesday called the case an "important national priority." Spokesman Josh Earnest downplayed the request, saying investigators were simply asking for a way in to this single device.

But Cook said there was no way to guarantee those limits, and that cracking this device "would undeniably create a backdoor" to all iPhones and other encrypted Apple devices.

"The US government has asked us for something we simply do not have, and something we consider too dangerous to create. They have asked us to build a backdoor to the iPhone," Cook said. Such a move would "undermine the very freedoms and liberty our government is meant to protect."

The implications of the government's demands are "chilling," he said because it would give the government the power to reach into anyone's device to capture their data.

The American Civil Liberties Union, the nation's leading legal rights group, praised Cook and said it would support Apple in the legal battle to come.

In a press release, the ACLU pointed out "if the FBI can force Apple to hack into iPhones, then so too can every repressive regime in the world."

Fugitive cyberspying whistle-blower Edward Snowden agreed. In a message on Twitter he wrote, "the FBI is creating a world where citizens rely on Apple to defend their rights, rather than the other way around."

Snowden said the software the FBI is demanding would enable iPhone encryption to be cracked in half an hour.

The issue of encryption has been a source of tension between technology companies and law enforcement for decades.

Tech producers build in encryption to protect customers' privacy. In some cases the companies themselves cannot even crack the encryption.

But the ability to communicate without fear of government surveillance potentially creates cover for criminals and terrorists too.

Cook's letter said Apple already had done everything in its power and within the law to help the FBI.

"Opposing this order is not something we take lightly," Cook wrote. "We feel we must speak up in the face of what we see as an overreach by the US government."

Related stories

Google, WhatsApp back Apple in encryption fight with FBI

Apple and FBI to face off in court

Apple: Court must reverse "dangerous" FBI order

FBI opens iPhone without Apple's help

Gates breaks with Apple, Google on FBI phone order

Apple case delayed as FBI tries its own iPhone hack

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.