The New York Post said some of its Twitter accounts were hacked on Friday, in the wake of a series of inaccurate posts on the social network relating to the Federal Reserve, Bank of America and U.S. military engagement with China.

Similarly peculiar messages appeared on a Twitter account controlled by United Press International.

"Some New York Post Twitter accounts were briefly hacked and the matter is being investigated," the Post said in a statement issued through a public relations firm.

A message appeared for a short time on the Post's "@NYPostBiz" account, which focuses on business news, reading: "Our Twitter feed has been hacked." The message was deleted soon after, and its authorship was unclear.

The message on the UPI account included one saying that Pope Francis had announced the start of "World War III."

Those messages remained on the "@UPI" Twitter feed early on Friday afternoon.

UPI could not immediately be reached for comment.