Protesters trying to topple Thailand's government said they would tighten the blockade around ministries on Tuesday and a hardline faction threatened to storm the stock exchange, while many major intersections in the capital Bangkok remained blocked.
The turmoil is the latest chapter in an eight-year conflict pitting the Bangkok-based middle class and royalist establishment against the mostly poorer, rural supporters of Prime Minister Yingluck Shinawatra and her brother, Thaksin Shinawatra, a former premier who was ousted by the military in 2006.
Many ministries and the central bank were forced to work from back-up offices on Monday after protesters led by Suthep Thaugsuban stopped civil servants getting to work.
''We must surround government buildings, closing them in the morning and leaving in the afternoon,'' Suthep told supporters late on Monday, urging them to do that every day until Yingluck steps down.
A student group allied to Suthep's People's Democratic Reform Committee has threatened to attack the stock exchange, with faction leader Nitithorn Lamlua telling supporters on Monday it represented ''a wicked capitalist system that provided the path for Thaksin to become a billionaire''.
However, there was no special security visible at the building early on Tuesday.
A Reuters photographer said one group of protesters marched past on their way to the customs department but did not stop.
Jarumporn Chotikasathien, president of the Stock Exchange of Thailand, told Reuters emergency measures had been prepared to secure both the premises and trading systems if needed.
The potential disruption to government services would compound the problems faced by Yingluck, who dissolved parliament in December and called a snap election for February.
Even though she had a commanding majority in the legislature and is likely to win again, she now heads a caretaker administration that has a limited remit and cannot initiate policies that commit the next government.
Yingluck worked on Monday from Defence Ministry facilities in the outskirts of Bangkok. Officials said that Tuesday's regular cabinet meeting had been cancelled.
Yingluck invited protest leaders and political parties to a meeting on Wednesday to discuss an Election Commision proposal to postpone the election until May.
However, Suthep has repeatedly said he is not interested in any election.
He wants the government to be replaced by an unelected ''people's council'' that will change the electoral system as part of reforms that will weaken Thaksin's sway.
Thaksin turned to politics after making a fortune in telecommunications.
He redrew Thailand's political map by courting rural voters and won back-to-back elections in 2001 and 2005.
Thaksin lives in exile to avoid a jail sentence handed down in 2008 for abuse of power, but he is seen as the power behind Yingluck's government.
Their Puea Thai Party seems likely to win any election held under present arrangements.
Traffic in Bangkok remained light on Tuesday, with seven big intersections blocked by protesters the day before.
Many schools stayed shut on Tuesday for the second day.
On Monday, several offices were also closed and many commuters stayed at home, so even the roads that were open saw unusually light traffic.
The government has deployed 10,000 police to maintain law and order, along with 8,000 soldiers at government offices, but they were practically invisible on the streets on Monday.
Ministers have said they want to avoid confrontation, hoping the protest movement will eventually run out of steam.
It flared up at the start of November when the government tried to force through a political amnesty that would have allowed Thaksin to return home a free man.