Twitter accounts belonging to the United Press International and the New York Post were hacked Friday afternoon.

Both news agencies sent erroneous tweets indicating that China had taken military action against the U.S.

UPDATE: @UPI Twitter account still has tweets that appear to have been published as the result of a hack. pic.twitter.com/8CJFEd2vtA

— Josiah Daniel Ryan (@JosiahRyan) January 16, 2015

Looks like @upi hacked: pic.twitter.com/0EopepZplf

— Jonathon M. Seidl (@jonseidl) January 16, 2015

The @nypost looks like it's been hacked. pic.twitter.com/HDkCUEzfvp

— Nick Turner (@SFNick) January 16, 2015

The tweets were almost immediately deleted. The two outlets then confirmed what had just happened.

.@UPI website, Twitter account hacked along with @nypost http://t.co/8t6w1i2qGy (World War III has not started, thankfully)

— UPI.com (@UPI) January 16, 2015

Our Twitter account was briefly hacked and we are investigating.

— New York Post (@nypost) January 16, 2015

Our Twitter account was briefly hacked and we are investigating.

— NY Post Business (@nypostbiz) January 16, 2015

Pentagon press secretary Rear Adm. John Kirby, responded to the false report that the USS George Washington, in fact, had not been struck by a Chinese missile, USA Today reported.

"I can assure you and everybody else that the USS George Washington is safe and sound in drydock," where it is getting needed maintenance. She has not been attacked by anybody," Kirby told USAToday.

Twitter users seemed skeptical from the beginning:

UPI and New York Post Twitter feeds seem to have been hacked. Or we're at war with China ¯\_(�)_/¯

— Matt Wahnsiedler (@MattWahnsiedler) January 16, 2015

WTF? Pls tell me @NYPost Twitter account was hacked. @UPI, media publishers: Watch your Twitter feeds carefully. pic.twitter.com/vxgTTnB3bA

— Jennifer Barrett (@JBarrettNYC) January 16, 2015

Someone hacked @nypost or we're now at war with China. pic.twitter.com/BWfqRqojHY

— Dave Rubin (@RubinReport) January 16, 2015

Both @UPI and @nypost appear to have been hacked and pumping out fake newz

— Raf Sanchez (@rafsanchez) January 16, 2015

The cyberattacks came just minutes after President Barack Obama and British Prime Minister David Cameron concluded a joint White House press conference during which they discussed a whole range of topics; among them, cybersecurity.

On Monday, U.S. Central Command's Twitter feed was hacked. The act of "cybervandalism," as the department of defense agency later called it, was just another wake up call following a slew of other cyberattacks on private-sector companies such as Sony and Microsoft.

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