The BSF Friday seized 13 kg heroin after a gun battle with Pakistani smugglers in Ferozepur sector of the India-Pakistan border in Punjab, an official said.The heroin consignment is estimated at Rs.65 crore in the international market.A Border Security Force (BSF) spokesman said the seizure was made near the Satpal border outpost in Ferozepur sector, about 300 km from here.BSF troopers noticed some movement in the area near the international border Thursday night. The smugglers were challenged but they opened fire at the BSF troops. The fire was returned but the smugglers escaped under the cover of dense fog and darkness.The drugs were recovered Friday. The BSF also recovered a pistol and ammunition from the area.The BSF has recovered over 25 kg heroin along the international border in Punjab this year. Over 18 kg has been recovered in Ferozepur alone.The BSF had last year seized over 361 kg of heroin in the Punjab sector. This was the highest seizure in the Punjab sector by the BSF.