The BSF on Wednesday seized 900 grams of contraband suspected to be heroin from near the India-Bangladesh border in Murshidabad district.Acting on a tip, personnel from the fourth battalion of the Border Security Force launched a special patrol near the Diar Manik Chak outpost in Lalgola area and found a man suspiciously approaching the border fence from the Bangladesh side.On being challenged, the man left behind a bag and escaped taking advantage of the fog, a BSF officer said.The special patrol ream conducted a thorough search and found a plastic bag from which nine packets of a light brown coloured powder -- weighing 900 grams -- was seized and handed over to the Narcotics Control Bureau in Kolkata for investigation.This year, the BSF South Bengal Frontier has seized 1,550 grams of narcotics and apprehended three smugglers.