White House: Sony Hack 'Still Under Investigation'

WASHINGTON--The White House on Thursday said the hack into Sony Pictures computers was carried out by a sophisticated actor and is being treated as a serious national security issue.

Speaking to reporters on Thursday, White House press secretary Josh Earnest said the investigation was still under way and the U.S. was weighing a "proportional" response to the attacks. "There are a range of options that are under consideration right now," Mr. Earnest said.

Mr. Earnest echoed earlier comments by U.S. Homeland Security Secretary Jeh Johnson, who said the U.S. is weighing a "range of options" to respond.

Amid threats of violence and an unprecedented corporate hacking, Sony Pictures, the studio unit of Sony Corp., said it would cancel the showing of the film "The Interview," which depicts a fictional assassination plot of North Korean leader Kim Jong-un.

U.S. officials have concluded the North Korean government in Pyongyang was behind the hacking attack, but Mr. Earnest said he wasn't prepared to publicly make that determination.

The White House said President Barack Obama's senior advisers from the intelligence community, military and diplomatic community were having daily meetings about the situation.

The president and the Obama administration stands "squarely on the side of artists and other private citizens who seek to freely express their views," Mr. Earnest said.

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