"His Holiness Somdet Phra Nyanasamvara, the Supreme Patriarch of Thailand, passed away at King Chulalongkorn Memorial Hospital" Thursday evening, the Thai government said on its website. The report said the hospital announced he had died of blood infection.
The announcement said he underwent an operation Oct. 14 to remove portions of his intestines after being diagnosed with a bacterial infection. "His condition remained stable and then worsened following the surgery," it said, adding he had been ill since 2002.
The Supreme Patriarch had turned 100 on Oct. 3 and had been the longest living Supreme Patriarch in the history of the country, a predominantly Buddhist country.
The government ordered the national flag to fly at half-mast through Sunday and instructed all civil servants and government employees to war unadorned black clothing during the 15-day mourning period beginning Friday.
The Bangkok Nation said the Supreme Patriarch was the mentor of Thai King, His Majesty Bhumibol Adulyadej during his 15-day ordination in 1956.
"The passing away of His Holiness, the 19th Supreme Patriarch of the Rattanakosin period, has brought great sorrow to the Thai people," the government announcement said.
The Thai monarch ordered the body of departed Buddhist monk be placed at Phra Tamnak Phet (Royal Diamond Residence) at Wat Bovoranives in Bangkok and that the memorial rite be held in accordance with the royal tradition.
"His Holiness was the longest living Supreme Patriarch in Thai history. Born on Oct. 3, 1913 in Kanchanaburi province, he was formerly known as Charoen Gajavatra," the government announcement said.
After completing his elementary education, he was ordained at the age of 14 in his hometown. He moved to Wat Bovoranives in Bangkok in 1929 to further his Pali and Dhamma studies.
The patriarch, widely revered by Buddhists around the world, was proficient in Pali, Sanskrit and English languages. He also studied German and French, and Chinese.
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