Former House Speaker Newt Gingrich marked the 75th anniversary of the attack on Pearl Harbor by hailing what he called Japan's "professional brilliance and technological power."

The curiously-worded tribute came in a series of tweets on Wednesday in which Gingrich cautioned that "surprise is possible even when we have been warned."

The questionable phrasing of his tweets, which appear to praise Japan for the attack, infuriated Twitter users:

More than 2,400 Americans were killed on December 7, 1941, when Japan attacked the US naval base at Pearl Harbor in Hawaii, leading the US to enter World War II.

Gingrich was an early supporter of President-elect Donald Trump, and for a time was on Trump's shortlist for vice president. Last month, Gingrich said he will not serve in Trump's Cabinet.