According to officials reports, trade union affiliated with former communist rebels attacked Nepal's largest newspaper office, destroying property and grounding publication to a halt.
The Kantipur Publication, which publishes the privately run Nepali-language newspaper Kantipur and English edition The Kathmandu Post, was attacked by supporters of the All Nepal Printing and Publication Workers' Union, a wing of the former communist rebels.
The managing director of the publication, Kailash Sirohiya, said union activists tried to attack him, vandalized his vehicle and locked the newspaper office on Sunday. The activists also vandalized the printing press at night, forcing the company to stop publication of the newspapers.
Sirohiya said it would take a week for repairs before they can begin operation.
"This is a planned attack on the free press in the name of union demands," Sirohiya said.
The union had been protesting, demanding their members be given permanent jobs at the publications, better positions and pay raises.
Police official Gorakh Bhandari confirmed the attack and said two of the attackers were arrested.
The Federation of Nepalese Journalists has condemned the attack.
"This is continuation to attacks on the free media by the Maoists despite assurances by their leaders in the past," said Bishnu Nisthuri of the federation.
Comment from the union was not immediately available Monday.
The newspapers are known to be critical of the continued violence and abuses allegedly perpetrated by the former rebels.
Kantipur Publication is part of the largest news group in Nepal, which also has a television station, a radio station, several magazines and an online news portal.
The ex-rebels, known as Maoists, joined a peace process last year and abandoned their armed revolt, which began in 1996 and resulted in the deaths of 13,000 people.
They have been accused of continuing violence, however, including attacks on media outlets, businesses and government offices.