Pearl Harbor's 70th anniversary remembered in US
The Pearl Harbor attacks' few remaining survivors have led US commemorations of the 70th anniversary of the event that changed World War II's course.
About 120 veterans joined military leaders at the Hawaii naval base as a moment of silence was observed at the time Japan sprung its offensive.
President Barack Obama called for US flags to be flown at half mast on federal buildings across the country.
Some 2,400 Americans died in the Japanese attacks of 7 December 1941.
President Obama, who was born in Hawaii, hailed veterans of the bombing in a statement marking National Pearl Harbor Remembrance Day.
"Their tenacity helped define the Greatest Generation and their valour fortified all who served during World War II," he said.
"As a nation, we look to December 7 1941 to draw strength from the example set by these patriots and to honour all who have sacrificed for our freedoms."
At 7:55 am (17:55 GMT), the moment Japanese bombers swooped on the US Pacific Fleet at Pearl Harbor, a ceremony was held by the wreck of the USS Arizona, one of 12 vessels sunk that day seven decades ago.
Nearly half of those killed in the attack died almost instantly on the Arizona, when a bomb detonated the giant battleship's munitions.
Navy Secretary Ray Mabus and military leaders were also among the several thousand people at Wednesday's event.
A US Navy destroyer rendered honours to the Arizona to begin the moment of silence, before F-22 jets flew overhead in "missing man" formation.
Over in Washington DC, Defence Secretary Leon Panetta laid a wreath at the US Navy Memorial at midday.
The Pearl Harbor Survivors Association said it would disband after this year's landmark commemoration because so few veterans remained.
Thousands of survivors were on hand for the 50th anniversary of the attacks in 1991.
As well as the dozen ships wrecked in the attack on Pearl Harbor, nine other vessels were damaged and the US lost 164 aeroplanes. Sixty-two Japanese died.
Denouncing "a date which will live in infamy", President Franklin Roosevelt went to Congress for a declaration of war, which was approved within hours.
Three days later, Germany declared war on the US. America's entry was to change the course of the conflict.