The key defendant in the country's most sensational drug trial yesterday begged for mercy after failing to convince the court he had been smuggling bags of white confectionery - not heroin. Federal police captain Vu Xuan Truong asked for clemency for himself, his brother and wife, saying he feared for the future of his two children, court sources said. His mistress is also on trial but was not mentioned in the plea, which came at the end of a series of humiliations for Truong. Officials at the Hanoi People's Court scoffed when he suggested he stored more than five kilograms of heroin at his house for colleagues, court sources said. They then erupted into open laughter when Truong suggested he had given bags of white confectionary rather than heroin to police drivers to move from the mountainous Lai Chau province near Laos to Hanoi. Truong has been billed as the kingpin of an Interior Ministry-protected syndicate linked to the smuggling of an estimated 300 kg of Golden Triangle heroin into Vietnam. Some 11 police and four border guards are among 40 people arrested so far amid widespread public outrage at the involvement of the powerful Interior Ministry. Vietnamese courts work on the presumption of guilt and Truong's performance after three days suggests an almost certain death by firing squad. Truong earlier said he was ready to die if the lives of his relatives could be saved. He has also vowed to reveal the identities of 'extremely important people' who allowed his gang to flourish. The link to senior levels of the ministry means the trial is effectively being held behind closed doors with only carefully screened information appearing in Vietnam's state press. The case comes amid widespread concern at Vietnam's burgeoning role in the heroin trade. The glut of the drug on Hanoi's streets saw the National Assembly on Saturday pass tough laws for heroin trafficking as well as opium use and cultivation, practices traditionally ignored by authorities in mountain areas. After stiff debates actively joined by concerned mountain tribesmen, laws were passed stipulating life in jail or the death sentence for possessing 5 kg of opium or 100 grams of heroin.