( CNN ) -- Tourists arriving in Bangkok may expect to see troops guarding key buildings and intersections , while masked vigilante protesters patrol their own roadblocks built from sandbags , barbed wire , rubber tires and debris . Bangkok 's political violence has been escalating , and at least 21 people have died since anti-government protests began in November . Some of the capital 's popular tourist areas -- including upmarket Sukhumvit Road where hotels , restaurants , shopping malls and other facilities remain open for business -- are now ground zero for the loud and crowded protests . They have blockaded some sections of Sukhumvit Road , and are also camping in nearby Lumpini Park , plus other sites . At night , gunfire and grenades echo in some central areas of Bangkok , making it unwise to stay out too late or go to places where protesters gather . Seasoned travelers should be able to figure out where and when not to go , and can follow Twitter feeds about the security situation on # Thailand and # BKKShutdown , plus many countries ' online travel advisories . Dozens of countries issued travel warnings in recent weeks about Thailand , including the U.S. State Department . `` Although many protest activities have been peaceful , violent incidents involving guns and explosive devices have occurred at or near protest sites . Some have resulted in injury or death , '' advised the latest U.S. State Department warning , updated on Feb. 14 . `` In Bangkok , protests have been mobile throughout the city , with large numbers of demonstrators at times swelling quickly and closing major roads and intersections , '' it said . What to expect . Travelers visiting a chaotic developing country for the first time may feel nervous when their taxi is stopped by angry masked men who might not get on well with the driver , because many taxi drivers are perceived to be against the protesters . International backpackers usually stay in Bangkok 's older neighborhoods in and around Khao San Road , which has experienced unrest but is generally sheltered . In fact , most of Bangkok is safe . But it could be dangerous to voice any opinion about Bangkok 's protests to Thais who visitors are not personally acquainted with . Emotions are so high that many families are now divided because of the political polarization . Tourism dipping . Bangkok 's two airports , serving international and domestic airlines , are open . No foreign tourists are known to have been injured in any clashes . However , some foreigners have expressed fear after encountering tough protesters barking orders or assaulting other Thais near rally sites . The government 's Tourism Authority of Thailand ( TAT ) tries to paint a pretty picture of the country 's gorgeous beaches and upcountry destinations , which some travelers agree are the best places to visit now . Many tourists are flying into Thailand but not to Bangkok , and instead choose international and domestic airports in Phuket , Chiang Mai and elsewhere either by direct flights from foreign countries or changing planes in Bangkok . `` Many tour groups from Asian countries such as China , Japan , Hong Kong and Vietnam do not want to come to Thailand , '' said TAT Governor Thawatchai Arunyik , according to the Bangkok Post . `` We estimate that we will lose up to 900,000 visitors during the first half of this year , '' Mr. Thawatchai said . Security concerns and delays . Avril Lavigne played in Bangkok on Feb. 11 without problems , but Eric Clapton canceled his upcoming March 2 performance due to security concerns . Travelers who are injured or have serious health problems may experience frustration as protesters ' blockades have delayed people trying to get to hospitals for emergency medical care . Thai government offices are also unable to quickly function because several ministries and other official buildings are under siege and locked by protesters , who forced officials to flee . Thai re-entry visas and extensions take more time to receive . The government however set up alternative offices in shopping malls , sports stadiums , convention centers and elsewhere to handle many of its bureaucratic backlogs . Visitors should not wear solid red-colored clothes , or buy the T-shirts now on sale in Bangkok which say `` Popcorn Army '' -- the two most inflammatory images identifying each side . Richard S. Ehrlich is a writer and journalist based in Bangkok .
Bangkok and parts of nearby prefectures remain under state of emergency following protests , violence . Tourists to Bangkok should remain on high alert . Comment: No foreign tourists have been injured in any clashes .