World Bulletin/News Desk

Thailand’s 86-year-old King remains hospitalized with an infected intestine, a month after the removal of his gallbladder, the royal household said in a statement Thursday.

Bhumibol Adulyadej experienced a recurring inflammation of a part of his large intestine, according to the statement published in Thai media.

He experienced abdominal pain and hyperventilation and developed a fever, which subsided when doctors at Siriraj Hospital in the capital Bangkok administered an antibiotic intravenously to treat the swelling.

Any sign of deterioration in the King’s health causes widespread anxiety in Thailand, where he is revered as a unifying figure and considered almost a semi-god.

Adulyadej ascended the throne in 1946, making him the world’s longest reigning monarch, beating the United Kingdom’s Queen Elizabeth II by a few months. He enjoys protection by law and social customs, the former of which carries a penalty of 15 years in jail for defamation under the country’s lese-majeste law.

The King has long been considered a pillar of Thai national identity, the twilight of his reign being feared by many Thais - the vast majority of whom were born under his rule.

His succession has been one of the more contentious points in the country’s politics over the last several years with a choice between two heirs - his eldest son, who has legal and traditional rights to the throne, and his second daughter, who enjoys popular support

Critics worry that an uncertain succession process could lead to more instability for a country that has suffered widespread political protest and two military coups in the last eight years, the latest on May 22 this year.

This week, Thai police banned imports of a book - "A Kingdom In Crisis" - by a British journalist, calling it "insulting to the country's monarchy."