Clashes erupted in south Nepal as Maoists began violent protests and closed down some districts, alleging a conspiracy by the governments of Nepal and India to sabotage the critical election next month by importing sophisticated weapons from India.
The Young Communist League, the dreaded youth wing of the Maoists, went on a rampage in Butwal, a key town in southern Rupandehi district, blocking the highway, setting police posts and at least one vehicle on fire and beating up two policemen on Tuesday.
The former rebels also called a dawn to dusk closure in three sensitive districts in the Terai that comprise their self-styled Avadh region - Rupandehi, Nawalparasi and Kapilavastu, the birthplace of the Buddha and yet one of the most turbulent regions in the country.
Nationwide protests have also been planned for an hour in the afternoon, including in the capital, where a large number of foreign dignitaries are camping as observers to ensure that the historic election on April 10 is free, fair and peaceful.
"We have called the protest as there has been a gross violation of the peace agreement," Devendra Poudel, chief of the Maoists' Avadh region, told IANS.
"We feel there is a conspiracy to sabotage the election."
The Maoists say they received a tip-off three days ago from their sources in the Nepal Army that consignments of arms and ammunition were pouring into Nepal through the Bhairahawa border point from the neighbouring Indian state of Uttar Pradesh.
On Monday night, Maoist MP Bamdev Chhetri and Sunil led a raid that they say netted two trucks with Uttar Pradesh number plates in Butwal while a third managed to evade the dragnet.
Nepal's Armed Police Force and civilian police, they say, were escorting the vehicles.
"We halted the two trucks for six hours, requesting human rights activists to come and check what they contained," Sunil said.
"But police attacked us and forcibly took the two vehicles away. Two dozen party men have been injured in the police attack."
While the Nepali authorities are saying that the trucks contained materials for the April 10 constituent assembly election, the Maoists allege they contain AK-47s and the Insas group of weapons indigenously manufactured by India.
The former rebels say that over three dozen such arms-laden trucks have already entered Nepal.
"This is a blatant violation of the peace pact (signed between the Maoists and the ruling parties two years ago that ended the Maoist insurgency and brought peace to Nepal)," said Maoist leader Prashant, who is contesting the April 10 constituent assembly election.
"It is part of a deep-rooted conspiracy to sabotage the election."
After the signing of the peace agreement, the new government of opposition parties agreed not to recruit any more soldiers or buy arms.
India has been Nepal's major arms supplier, providing the government with arms at a 70 percent subsidy to combat the Maoist insurgency that started in 1996.
However, after King Gyanendra seized power with the help of the army in 2005, India stopped the flow of arms to signal its displeasure.
With the king's regime collapsing 14 months later, there were talks of India resuming arms assistance.
A recent bilateral security meeting in New Delhi was reported to have focussed on fresh arms sales.
The Indian arms issue could snowball and affect the election, which is to decide the fate of King Gyanendra.
There is speculation that both the ruling parties and the Maoists are averse to the polls, fearing defeat.
The arms issue could be a bogey by the Maoists to block the twice-postponed polls.
On the other hand, India has come under intense criticism in Nepal for "meddling" in its internal matters.
In the past, while the Maoists were branded a terrorist organisation, India brokered a clandestine deal between them and the opposition parties in New Delhi.
After ethnic movements started in the Terai plains along the Indo-Nepal border, the Indian hand has been at work in Nepal once again, brokering an agreement between the government and dissident Terai parties.
The discovery that the chief of India's intelligence department Research and Analysis Wing Ashok Chaturvedi had paid a secret visit to Kathmandu and met Koirala created a furore.