The ultra-leftists, who renounced violence when they signed a peace deal last November, have attracted thousands of workers from sectors ranging from tourism to education.

The latest strike by a Maoist-affiliated union was on Tuesday, with 50,000 copies of a popular English language daily newspaper stuck at the printers due to a strike by delivery workers -- their second in a week.

The strike "is a part of the larger picture," said Ram Pradhan, editor of the Himalayan Times, the paper hit by the stoppage.

"It's more political than industrial. They (the Maoists) want to put pressure on all sectors and show how powerful they are," he said.

He senses that the Maoists are attempting to enlist broad support ahead of crucial elections set for November.

The vote, a key part of the peace process, will lead to formation of a body that will rewrite the constitution.

"These kind of actions," Pradhan warned of the union activity, could "endanger the peaceful transition that's supposed to be going on."

The tourism sector, a key foreign currency earner, has also been hit.

"The Maoists want to establish themselves and get recognised and that's why they've been building networks in almost every sector," said Prakash Shrestha, president of the Hotel Association of Nepal.

"We don't oppose formation of trade unions but they must be practical and know their rights and limitations. If we fulfilled their every demand, the institutions would collapse," he said.

Since emerging from the jungles after 10 years of brutal civil war, the Maoists have promised to join the mainstream.

Despite being given key government portfolios, allegations of mafia-style beatings and abductions persist.

The education sector has proved fertile ground for the former rebels to build their presence, with thousands of private schools shut down in May by another strike.