Protesters who have gathered en masse across Bangkok since Sunday vowed to take their movement to topple the government nationwide Wednesday in a sign that Thailand’s worst political crisis since 2010 may be far from over.

The protesters are demanding that Prime Minister Yingluck Shinawatra, who took office in 2011, step down amid claims that her government is, in fact, controlled by her brother, former Prime Minister Thaksin Shinawatra, who was ousted in a military coup in 2006 on charges of corruption.

Yingluck’s billionaire brother now lives in self-imposed exile in Dubai to avoid a prison term, though he argues his punishment was politically motivated. Demonstrations in Bangkok began Sunday with a rally over the proposed introduction of a political amnesty bill that protesters believe would spell Thaksin’s imminent return.

Tens of thousands of anti-government demonstrators have staged protests this week at three main areas: Democracy Monument on Ratchadamnoen Klang Avenue, Nang Lerng Junction on Nakhonsawan-Phitsanulok Roads and Sanam Luang on Ratchadamnoen Nai Avenue. They have also occupied the Ministry of Finance and the areas outside the Government Public Relations Department, the Ministry of Tourism and Sports, the Ministry of Agricultural and Cooperatives, and the Ministry of Transport.

Analysts say Thailand is now plunged into its worst political crisis since the bloody unrest in 2010 when at least 90 people were killed. Yingluck’s government has promised not to resort to violence to stop the current demonstrations.

At least 20 countries, including Britain, France, Germany, Japan, Canada and Brazil, have issued travel advisories urging citizens to avoid visiting areas near the protest camps in the capital. The U.S. Embassy in Bangkok also issued a message to American citizens in Thailand, warning that political unrest could continue for some time.

“Even demonstrations that are meant to be peaceful can turn confrontational and escalate into violence,” it said. “You should avoid areas of demonstrations, and exercise caution if in the vicinity of any large gatherings, protests or demonstrations. Be alert and aware of your surroundings and pay attention to local news media reports.”

The Tourism Authority of Thailand has been criticized in the past for not acknowledging unrest as a way to stave off any bad publicity for the “Land of Smiles.” The agency opted for a different approach this time around, offering candid information about the current protests through regular situation updates, all while assuring visitors that all is well.

“Tourists need not be alarmed of the presence of security forces and checkpoints in Bangkok. Police are deployed to provide security in the city [and] security has been stepped up to prevent ill-intentioned people from inciting violence,” TAT said in its latest update. “Tourists are advised to check travel routes and road traffic situations as well as avoid areas where crowds may gather.”

The tourism board assured visitors that all tourist attractions in and around Bangkok such as the Grand Place, the Temple of the Emerald Buddha, Vimanmek Mansion, Siam Paragon and river tours along the Chao Phraya River are open and operating as per normal, despite some difficulties in getting to them.

Suvarnabhumi Airport, Thailand’s main international hub, advised air travelers of possible heavy road traffic and a lack of taxis resulting from the protests. The airport told commuters to use public transport such as BTS SkyTrain, Airport Rail Link, public buses and vans, and allocate more time to get to and from the airport for arrivals and departures.

All domestic airports, the State Railway of Thailand and Transport Co., Ltd. (which operates inter-provincial bus service) reported operations as usual Tuesday.

“Life in Bangkok and all other areas of Thailand continues as per normal,” TAT noted. “Tourist attractions and activities as well as businesses in Bangkok and other provinces are not affected, and continue as usual.”

However, that could change on Wednesday when protesters move to occupy the Provincial Hall on the popular resort island (and opposition stronghold) of Phuket. Local paper Phuketwan suggests that similar protests could ripple out across the nation into places like Pattaya and Koh Samui, potentially causing real problems for international visitors.

Useful contact numbers:

Tourism Authority of Thailand Call Centre: 1672

Thai Traffic Police Call Centre: 1197      

Thai Tourist Police Call Centre:1155

Bangkok Tourism Division Call Centre: +66 (0) 2225 7612-4