Thailand’s ailing King Bhumibol Adulyadej made a rare public appearance Monday at a ceremony to swear in new judges. The world’s longest serving monarch was seen in public for the first time since September, after failing to show up for nationwide celebrations on his birthday earlier this month amid growing health concerns.

Bhumibol, a revered figure in Thailand, was seen on local television footage, sitting on a gold throne during the swearing-in ceremony. The ceremony was carried out at a Bangkok hospital where the 88-year-old has been admitted for various health conditions, including a lung infection and hydrocephalus, a build-up of cerebrospinal fluid that surrounds the brain. However, palace officials did not provide details on Bhumibol’s health Monday, BBC reported.

The king was last seen in September in a video released by the palace showing his visit to a shop in the hospital on his wheelchair. Bhumibol’s health condition cannot be discussed openly in the kingdom because the royal family is shielded by one of the world's toughest lese-majeste laws, Reuters reported. Prosecutions of those accused of defaming the royals have increased drastically since the military government took over after a 2014 coup.

Anxiety among Thais over the future of the country once Bhumibol's six-decade reign ends is seen as a factor in Thailand's intensifying political divide, according to Agence France-Presse.

In September, a newspaper printer in Thailand declined to publish the full edition of the daily International New York Times, sparking speculation over the king's health and overall fate of the monarchy. The Times story described the looming challenge of succession in the Thai monarchy. When Bhumibol passes away, the heir apparent to the throne is Maha Vajiralongkorn, "the jet-setting crown prince" with "a reputation as a playboy" and who "faces an uphill battle to win the trust and adoration his father has achieved," the Times wrote. But the well-liked crown princess, Maha Chakri Sirindhorn, is not eligible to take over. This has added to an ongoing discussion about "what kind of monarchy Thailand should have," the story read.