Kolkata, Sep 18 : Banned narcotics worth Rs 42 crore has been seized from Siliguri in North Bengal in a single day-operation that started Sunday noon and continued till this morning. The recoveries were made through raid and search operations in three separate places following which eight persons were arrested. Police sources said that following the raid and search operations, huge consignments of costly brown sugar were seized whose estimated market value would be to the tune of Rs 40 crore. "Apart from that, around two quintals of marijuana was also seized following the raid and search operations at the three places, whose estimated market value will be to the tune of Rs 2 crore," said an official of Siliguri Metropolitan Police who is aware of the entire development. Meanwhile, the commissioner of Siliguri Metropolitan Police C. Sudhakar told media persons that Siliguri, because of its geographical advantage of being an important gateway in north Bengal, often becomes the target for the smuggling rackets including those dealing in narcotics trafficking. But we are determined to carry out our drives against this narcotics menace and the drive will continue in the coming days as well, he said. It is learnt that the eight arrested persons will be presented at a district court on Monday where the public prosecutor will seek their police custody. "Those arrested are mere cogs in the wheel and the main brains are surely operating from underground. The interrogation of the arrested persons is necessary so that we reach up to the main brains," the Siliguri Metropolitan Police official said. /IANS