The Anti-Narcotics Force (ANF) on Sunday arrested four suspects involved in drug trafficking from different cities.
ANF spokesperson said more than three and a half kilograms of opium was recovered from two suspects, including a woman, in an operation near Islamabad Motorway Toll Plaza.
ANF officials recovered 45 heroin-filled capsules and one caffeine-filled capsule from a suspect's stomach at Islamabad International Airport, he added.
According to the spokesperson, 75 narcotic tablets were also recovered from an accused who was a resident of Karachi. Legal action has been initiated against the arrested suspects, he said.