It is Saturday night on a Thamel side-street. Five young men walking along are suddenly confronted by 50 Maoists in five vehicles.

"We are Maoists," they say, "we are patrolling the streets for your protection."

Earlier that evening, Kumar Lama of Swoyambhu was taken into Maoist custody for drinking and starting a fight. His captors took him to the Maoist trade union office in Balaju where, according to the union's district chief Hom Bahadur Acharya, Lama was made to "understand and repent his action".

Lama returned home after three days badly bruised and unable to walk. "I had a little too much to drink and got into an argument with a taxi driver, that's why they took me," he recalled, "There were others there too, some of them were blindfolded."

Even as the peace talks were going on in Baluwatar, Maoists had begun patrolling the capital's increasingly crime-ridden streets. It may be against the 25-point ceasefire code of conduct, but that doesn't deter the Maoists from what they say is an effort to curb the crime surge.

The Maoist leaders want to keep their cadre busy, or it may be part of the party's hearts-and-minds campaign. But the end result is that the Maoists are meting out summary justice to anyone behaving in a rowdy manner on the streets.

The Maoists are also said to have taken some leaders of the Valley's criminal gangs into custody, although the rebels did not confirm it.

"We have been conducting patrols for the last three weeks and have taken some people into custody for action," said Pawan Man Shrestha of the Maoist-aligned Newar front, "those found guilty will be handed over to the police after investigations."

At the Maoist trade union office in Balaju we were told that the office was only a shelter for union members and that they were not holding any detainees.

But this is little consolation for Renuka Shrestha, whose contractor husband Rajesh and four friends were taken in by Maoists on the Ring Road on Wednesday morning. She asked around and was told to go to the Balaju office, where we met her.

"His father and mother are worried sick," said Renuka in tears after recognising her husband's motorcycle in the union's premises, "if he has done anything wrong take action, but at least let me meet him and see if he is all right." Union leader Acharya flatly denied knowledge of Rajesh's whereabouts.

Ceasefire monitoring committee member Taranath Dahal told us: "We have heard rumours that the Maoists are arresting people and holding their people's courts in the Valley. We are investigating, but if true it is a violation of the code of conduct and a breach of Prachanda's public commitment to not hold people's courts in cities."