The health of Thailand's King Bhumibol Adulyadej is "still unstable", the palace said late on Wednesday, with the 88-year-old on a ventilator and battling a new infection as crowds gathered to pray outside his Bangkok hospital.
Bhumibol is the world's longest-reigning monarch and beloved by many in Thailand, where he is seen as a rare unifying figure in a country riven by political rivalries.
But he has not been seen by the public for nearly a year as he battles a series of ailments in a Bangkok hospital, a source of great anxiety for many in the kingdom.
In a fresh palace health update released on Wednesday evening, blood tests on Tuesday showed the king's liver was working "irregularly" and that there was heightened levels of uric acid in his blood.
Doctors prescribed antibiotics for an infection, placed him on a ventilator and are using Continuous Renal Replacement Therapy (CRRT) to help lower acid levels, the statement said.
"His illness overall is still unstable," it added.
The statement followed a similarly pessimistic palace health update on Sunday that triggered market jitters inside Thailand this week as well as public prayers for his well-being.
By late evening around 300 well-wishers had gathered outside Siriraj Hospital where the king has spent much of the past two years.
Many held aloft portraits of the king and were moved to tears by a week of grim news.
"It feels like he is getting worse this time," said Somchit Naravichit, 58, tears welling in her eyes.
"Millions of Thais are sending him support, praying for him and wanting him to get well soon," she told AFP.
Market jitters 
Stock market volatility hit Thailand for a third day on Wednesday, plunging as much as 6.8% after junta chief General Prayut Chan-O-Cha abruptly cancelled a visit outside the capital with little explanation.
The market later recovered to close 2.5% down. But rumours about the king's health swirled on social media.
By late afternoon junta officials downplayed Prayut's schedule interruption saying he had returned to the capital to meet with named heir Crown Prince Maha Vajiralongkorn, who spends much time outside the country.
Junta spokesman Lieutenant General Sansern Kaewkamnerd said the trip cancellation was to provide the Crown Prince with "a routine presentation on the government's work".
Bhumibol's health is a sensitive subject and palace officials maintain tight control over news about his condition.
A draconian lese majeste law also makes public discussion of the succession all but impossible.
Privately many business leaders -- both domestic and foreign -- fret that the king's demise could lead to economic instability, especially as there is no official discussion on how the country will handle his passing.
Thailand's stock market has dropped by 6.5% since Sunday's health announcement and the baht has also dropped.
Since Sunday's announcement, many Thais have started wearing pink in the belief it will bring the king good luck.
Security was stepped up at the riverside hospital where Bhumibol is being treated, with a spokeswoman saying they expected the Crown Prince to make an imminent visit to see his father.