BANGKOK - Thai anti-government protesters are vowing to "shut down" Bangkok Monday in an effort to prevent upcoming elections and topple the government as the country's political crisis teeters on the brink of a tumultuous new phase.
Opposition demonstrators began massing at sites across the city over the weekend in their latest push to force Prime Minister Yingluck Shinawatra from office and deal a blow to the power of her divisive brother Thaksin -- a former premier ousted in a 2006 coup.
The protesters began blocking major intersections in the capital late Sunday as they looked to ramp up their rallies, in the run up to the February 2 elections which they have set out to disrupt.
They have also vowed to stop officials going to work and cut off power to key state offices as part of the shutdown efforts, which authorities have warned could lead to further bloodshed.
Eight people, including a policeman, have been killed and dozens injured in street violence since the protests began over two months ago.
"It's going to be very volatile," said Pavin Chachavalpongpun, a former Thai diplomat and associate professor at the Centre for Southeast Asian Studies at Japan's Kyoto University.
He said there was a risk of "political violence" with protesters under pressure to achieve their objective of removing the government before the election, which would likely return Yingluck and her party to power.
"In a way there is no turning back for the protesters they have come too far," he added.
The current political crisis is the latest chapter in a saga of political instability and occasional unrest that has gripped Thailand since Thaksin was ousted from power by royalist generals seven years ago.
The billionaire tycoon-turned-politician, who lives abroad to avoid a jail term for corruption, has large electoral support particularly in northern Thailand, where he is adored for a swathe of popular policies.
But he is reviled among the country's elites and by many in the Bangkok middle class and Thai south, who see him as authoritarian and accuse him of buying votes.
The protesters want an appointed "people's council" to run the country and oversee vaguely defined electoral reforms before new elections are held in around a year to 18 months.
The civil strife is the worst since 2010, when more than 90 people were killed in street clashes between pro-Thaksin protesters and the military.
Authorities say they are ready to declare a state of emergency if there is fresh unrest, and roughly 20,000 police and soldiers will be deployed for security.
Police said there were 12 hospitals, 28 hotels, 24 schools and five fire stations within the areas affected.
They estimate that 700,000 vehicles travel past the seven planned protest sites on a normal day in the congested Thai capital.
Thai stocks and the baht currency have fallen sharply on concerns that the latest turmoil will scare off tourists and investors.
Enterprising street vendors have begun selling a wide variety of "Bangkok shutdown" themed t-shirts along with a plethora of merchandise in the red, white and blue of the Thai flag.
"Initially, we will stay until February 2. We are confident the election will not take place," Thavorn Senniem, one of the rally leaders, told AFP on Sunday as protesters began to mobilise across the city.
The US embassy has advised stockpiling a two weeks' supply of food, water and medicine.