TOKYO -- Japan's Emperor Hirohito, the last of the major leaders of World War II who saw his defeated country reborn as an economic superpower, died early Saturday after a 111-day battle with cancer, unleashing a massive and spontaneous outpouring of public grief.
Crown Prince Akihito, 55, immediately succeeded the 87-year-old Hirohito as the 125th emperor on Japan's 2,600-year-old Chrysanthemum Throne, the world's oldest imperial line.
Hundreds of thousands of Japanese, many weeping opening and bowing in reverence, swarmed the palace grounds throughout the day to mourn the longest reigning monarch in the nation's history.
The government of Japan announced that Akihito's reign will be called 'Heisei,' a term taken from ancient Chinese documents meaning 'the achievement of complete peace on Earth and in heaven.' Hirohito's era was called 'Showa,' or Enlightened Peace.
Hirohito -- who ascended to the throne 62 years ago as a living god only to be reduced to a powerless symbol of state in the wake of Japan's World War II defeat -- died at 6:33 a.m. (4:33 p.m. EST Friday), said Imperial Household Agency Grand Steward Shoichi Fujimori.
'He died of a malignant tumor of the duodenum,' he said. Takako Shimazu, one of Hirohito's five daughters, said the emperor 'died peacefully.'
Hirohito, the last surviving major leader of the World War II era and the world's oldest and longest currently reigning monarch, died in his bed at Tokyo's moated Imperial Palace after lapsing into critical condition hours earlier.
The frail monarch -- his 5-foot-3 frame weighed just 50 pounds at his death -- had been kept alive with almost daily blood transfusions administered by a team of five court physicians since a relapse of his disease Sept. 19.
After the emperor's death, the court doctors washed the monarch's body and purified his clothing, the palace spokesman said. An autopsy would be performed, he said.
Hundreds of thousands of people, including the older generation who once worshiped Hirohito as a living god and children who have only read of the emperor in history books, streamed to the palace aboard trains, subways and on foot after the announcement of his death.
Young and old weeped openly. Many bowed their heads in reverence. The palace erected 10 tents for mourners to sign their names to condolance registers.
David Bailey, 55, a professor of a New York state university currently studying in Japan, said, 'from the bottom of my heart I mourn the death of Emperor Hirohito.'
'The American people generally like the emperor,' Bailey said. 'They think the emperor decided to end the war and they don't regard him as one of the war criminals.'
Miki Ebara, 21, said, 'I was surprised to find so many people out here. It means he was supported by the majority of the Japanese people.'
Flags throughout Japan flew at half-staff and an official two-day period of mourning began in which government offices, financial markets and many businesses will remain closed. All television commercials were suspended for two days, but entertainment and sports programs were to be broadcast as scheduled.
The government said entertainment activities for civil servants, including events with dancing and singing, would be suspended for six days and the private sector also was asked to refrain from such events for two days.
Palace guards were placed on a special alert around the rambling imperial palace grounds dominating the heart of central Tokyo to prevent possible disturbances by left-wing radicals seeking to abolish the monarchy. Police also conducted spot checks of vehicles around the perimeter.
Leftist groups announced they would demonstrate in Tokyo and the western city of Osaka to protest the monarchy.
Police officials also said they were keeping a close watch on pro-monarchy rightists amid fears some may commit ritual suicides in anguish over the emperor's death in a bid to stir up a nationalistic fervor.
Four hours after the emperor's death, Akihito took possession of the sacred symbols of the monarchy -- a mirror, a sword and the 'Magatama,' comma-shaped ancient jewels.
A soft-spoken liberal, Akihito is the first emperor to ascend to the throne as a mortal after Hirohito was stripped of his divinity as 'Son of the Sun Goddess' following Japan's World War II defeat.
Akihito and his wife, Michiko, the new empress, had rushed to Hirohito's bedside Saturday morning and were with him when he died, along with other members of the Imperial family and Prime Minister Norobu Takeshita, the palace said.
'The sad news of the passing of his late Majesty the Emperor has left me grief-stricken,' Takeshita said. 'We had been hoping with all our hearts for the emperor's recovery. We extend our deepest condolences to the new emperor and share with him our sadness.'
Takeshita said World War II 'broke out against Hirohito's will' and praised him as the symbol of the nation's unity in the post-war recovery.
He said the emperor's efforts 'after the war to comfort the bewildered people living in desolation and inspire them with the courage to work for the rehabilitation of the nation, remain deeply impressed in the hearts of our people.'
Hirohito to ascended the throne on Christmas Day 1926, becoming at age 26 a living god in the eyes of the Japanese, and remained emperor longer than any of his 123 predecessors in the 2,600-year history of the Chrysanthemum Throne.
Hirohito's name was used as a rallying cry by the military Japanese government as it marched across Asia on the way to launching a surprise attack on the U.S. Navy at Pearl Harbor Dec. 7, 1941.
Although he was Japan's supreme leader, Hirohito escaped arrest as a war criminal after Japan's defeat in 1945.
But he was stripped of his mythical divinity and reduced to a powerless symbol of state under a postwar constitution largely written by the Allied Occupation Forces under Gen. Douglas MacArthur.
Hirohito, cherished by most Japanese as the father of modern Japan, said living to watch Japan's rebirth from defeat into the world's second leading economicpower gave him the greatest happiness of his life.
Sheltered for most of his life behind the moated walls of the palace in the heart of Tokyo, Hirohito never told the full story of his involvement in the war.
In recent years, the stooped and bespectacled emperor rarely appeared in public and spent much of his time studying marine biology, tending to his garden or watching television.
Akihito, who is said to favor opening up the imperial institution, took over the emperor's duties Sept. 22 and officially became the 125th emperor at the moment of Hirohito's death.
Hirohito had steadily weakened since undergoing intestinal surgery in September 1987 to remove an egg-sized growth in his pancreas. He was the first emperor in Japan's history to undergo surgery.
A year later, on the night of Sept. 19, the emperor vomited blood in his sleep, signaling the beginning of the health crisis that preceeded his death.
After the operation, a team of four physicians and six nurses were assigned to monitor the emperor's condition in his specially equipped, second-floor palace bedroom.
He had showed signs of recovering, taking short walks, some outdoors, and was well enough to travel to the imperial villa in the countryside with his wife, Empress Nagako, in July to escape Tokyo's summer heat. But he continued to lose weight.
Nagako, 85, now the empress dowager, is suffering from hip trouble and has not appeared in public for several years. Palace officials made no mention of her in Saturday's announcements.
The palace had refused to tell the emperor or the public that he was suffering from cancer, in keeping with the Japanese custom of not informing patients of life-threatening diseases. The palace confirmed the cancer for the first time in announcing his death.
'My heart still aches (for those killed in World War II),' were Hirohito's last public words, uttered in a weak voice on Aug. 15 during an annual memorial service.