Three separatist guerrillas were killed overnight in Kupwara district in Jammu and Kashmir when the army foiled an infiltration bid on the line of control (LoC), a defence official said on Monday."Suspicious movement was noticed by alert troops in Keran sector of the LoC yesterday (Sunday) evening," a defence spokesman said in Srinagar."Upon being challenged, a group of heavily armed terrorists opened fire resulting in an encounter that lasted for several hours. Three terrorists were killed in this encounter whose bodies have been recovered in searches after the gunfight ended," the spokesperson said. "Three AK-47 rifles, 12 AK magazines, 300 rounds of AK ammunition and two under barrel grenade launchers (UBGLs) were also recovered from the slain terrorists," the defence official added.