Thailand's anti-government protests, now in their third month, have taken a heavy toll on tourism in the bustling capital Bangkok, but sparked an upturn in arrivals at beach and mountain resorts, officials say.

Thousands of demonstrators have occupied areas near Bangkok's commercial and retail districts, paralysing traffic and causing logistical headaches for residents and visitors alike.

Ten people have been killed in sporadic outbursts of violence since late November.

Thailand attracted a record 26 million-plus visitors last year, up 19.63 percent from a year earlier, but arrivals fell by half to about one million in January from December.

The tourist high season runs from November to January, but the hotel occupancy in the capital is hovering at about 50 percent, according to the Thai Hotel Association, well below the usual 80 percent occupancy rate.

"Some hotels in the capital and near Bangkok are less than 50 percent full," Tourism Minister Somsak Phurisisak told Reuters. "This is highly unusual."

China and the United States have warned their nationals to avoid protest areas in the city, which are near some of the top five-star hotels and raunchy bar and entertainment districts, prompting some business people to stay away.

"They are afraid of inconvenience and afraid for their own safety," said Surapong Techruvichit, president of the Thai Hotels Association.

The protest areas have been turned into giant camp sites, complete with market stalls selling kitsch protest merchandise, making a quiet evening stroll next to impossible and prompting taxi drivers to drop their well-heeled fares far from their hotel.

Peak in mountains

The protesters, led by former deputy prime minister Suthep Thaugsuban, are in their third week of a "shut down" of the capital, though for the most part, it is business as usual.

Arrivals at Bangkok's main airport fell 4.3 percent in January compared with the same period as last year, according to the Airports of Thailand.

But many were heading instead for Thailand's famous beach and mountain resorts, such as Phuket, Krabi and Koh Samui.

Mountainous Chiang Mai, a backpacker's gateway to northern Thailand packed with crumbling Buddhist temples and hiking trails, is enjoying hotel occupancy of 95 percent.

"It's an impressive number for the hotel industry and the best we have seen in five years," said Phanut Thanalaopanich, president of the Thai Hotels Association northern chapter.

Tourism, which accounts for more than 8 percent of Southeast Asia's second-largest economy, has proved resilient in the past to political protests, some of them more deadly than the current standoff, but industry officials are worried that may not be the case this time.

The protests show no sign of ending soon and a prolonged siege of the capital could prove a real test to the economy and could deter new investors.

But some visitors to Bangkok, the world's most-visited city according to the MasterCard Global Destination Cities Index 2013, refused to be put off.

"We're in Bangkok for a night and then heading down south to party hard on an island," said Matthew Brown, who is visiting from Britain with university friends.

"It's been a pain getting around Bangkok, but it's hardly a war zone."