The nation has united in wishing His Majesty a full recovery as the government pleaded for calm and urged the public to rely on information from official channels amid concerns over the King's health.
Members of the royal family and a large number of well-wishers visited Siriraj Hospital last night where His Majesty the King is being treated.
Government spokesman Sansern Kaewkamnerd strongly denied a rumour that Prime Minister Prayut Chan-o-cha would make a statement yesterday.
The rumour was sparked when Gen Prayut cut short his visit to Chon Buri yesterday, where he was scheduled to meet government officials and private sector representatives in the eastern region, and assigned Deputy Prime Minister Somkid Jatusripitak to attend an afternoon function on his behalf.
Lt Gen Sansern said the premier left early to prepare for an audience with His Royal Highness Crown Prince Maha Vajiralongkorn.
The prime minister is to present a report on the government's work to the Crown Prince, he said.
Lt Gen Sansern said Gen Prayut had no plans for a press conference or to make a statement yesterday afternoon as reported in social media.
He urged the public to follow news and information through formal channels for accuracy and not to panic over information that comes from unverified sources.
Foreign news agencies' reports about the King's health led the Stock Exchange of Thailand's main index to fall 36.03 points, or 2.50%, closing at 1,406.18 points yesterday. It retreated as much as 6.9% before ending 2.5% lower.
Well-wishers, many of them in pink shirts, braved drizzle and fought traffic jams yesterday to express their wishes for His Majesty's speedy recovery at Siriraj Hospital. Many turned to social media and shared their best wishes in pink.
Donnapha Kladbupha, a 42-year-old English-language teacher, endured the traffic jams from her office on Bangkok's Rama III Road to the hospital after hearing a rumour about His Majesty's condition.
"I read messages about the King's health condition which were widely shared on Line and Facebook. I started feeling worried about his condition. I left the office right after I put down the phone into my bag. I called a taxi, but traffic was very heavy. So, I got out and reached here [Siriraj Hospital] by motorcycle taxi," Ms Donnapha recalled.
She said the taxi driver and the motorcycle taxi driver discussed the messages they had seen and shared the feelings of concern. "I cried on the way to the hospital; so did they," she said.
"His Majesty the King is the heart of Thailand. Without this heart, I wonder how our country can move on," said Ms Donnapha.
Her only wish at this moment is to see His Majesty's smile once again. "I know everyone will wish him a speedy recovery, but I want to see his smile after his recovery too.
"Never question the Thai people's love for their King. We love our King and we love each other too," she added.
Suwanna Kenamthiangwan, 62, from Bangkok, said: "I love the King very much and I would die for him."
Ms Suwanna and a group of 20 other people wearing pink shirts, a colour that is believed to have helped promote the King's well-being were chanting, "Long Live the King" while carrying his photographs.
"I will stop praying for him only when he gets better," she said, holding the King's A4-size photo close to her chest.
Mr Chaithat Piyacharoenkitchai, 59, who lives opposite the hospital, said he believes the King is going to be fine soon.
"The King once said he would live until he is 120 and I believe with all my heart that he can do it. He will live a long time with us," Mr Chaithat said, urging the public not to panic and think twice when receiving unofficial news on social media.
"The facts about His Majesty's health will only come from the Royal Household Bureau," he said.
Throughout the day, the King's health dominated the content read and shared by Thai social media users.
Thai and English translations of "Long Live the King" hashtags trended on Twitter while on Facebook, netizens shared their Buddhist prayers for the King's recovery.
Many people began changing their profile pictures or sharing photographs to convey their best wishes for His Majesty.
Some posted photographs of His Majesty taken at different times of his life, or images of themselves wearing yellow or pink to symbolise their best wishes for their beloved monarch, while others made merit.
Many people also posted songs and reports on how His Majesty has contributed to the country.
Thai expats living abroad also shared photos of themselves reciting prayers to wish the King a speedy recovery.
Popular mobile app Line also sent messages to its users requesting that they cooperate in not sharing rumours about the King's health.
A group of university students and members of the public recite prayers to wish His Majesty the King strength and good health. Patipat janthong
