Gorkhas, who are ethnic Nepalis, demand a separate "Gorkhaland" be carved out of West Bengal to protect their culture and heritage.

Supporters of the Gorkha Janmukti Morcha (Gorkha People's Liberation Front) urged tourists to leave the hills, a popular destination as temperatures soar on the plains below, to avoid getting caught up in the protests.

They have eased a ban on tourist buses for two days.

In the foothills to the south near the town of Siliguri, supporters of the ruling communist government of West Bengal said tourists had been beaten up by Gorkhas.

They called a parallel strike, blocked roads heading north and ransacked Nepali homes, officials and a Reuters photographer said.

"The communist government in the state is trying to starve us by cutting supplies," said Bimal Gurung, who is leading the Gorkha agitation.

"We will not back out from our demands and our agitation will continue peacefully."

Ethnic Nepalis were singled out and police used batons and tear gas to contain clashes in which dozens of people were injured, police said.

"The Gorkhas were chased away by the Bengali speaking people from the plains who are opposed to the statehood (demand)," K L Tamta, a senior police officer said.

The violence has badly hit another mainstay of the local economy, the region's vast tea gardens which ship highly-prized and fragrant brews around the world.

"This is the best time to pluck the high quality leaves, but the strike has hit us hard and we are losing 20 million rupees ($470,000) a day," Rajiv Lochan, secretary of the Siliguri Tea Traders' Association said.

At least 1,200 people died in the first Gorkhaland campaign in the 1980s, but protests ended a few years later after Gorkha leaders accepted limited autonomy.