"Acting on a tip-off, Pemba Tamang was arrested when he was trying to sell banned drugs. He was intercepted near Ghoom station around 4 pm today and a kg of heroin was seized from him," Superintendent of Police Kunal Aggarwal said.
Tamang, a resident of Magarjung village near Sukhiapokhri, was staying in a rented place at Sonada near here, he said.
Darjeeling police have arrested at least eight drug peddlers this year.
Aggarwal said Tamang had brought the drugs from an "international border" and was trying to send it to Nepal.