Delhi Police have arrested a 56-year-old alleged drug smuggler who had been absconding for eight years after being declared a proclaimed offender in a 2017 narcotics case involving the recovery of 4 kg of heroin, officials said on Friday.The accused, Darbara Singh alias Billa, a resident of Shaheed Bhagat Singh Nagar district in Punjab, was arrested from Patiala following sustained surveillance and intelligence gathering by the Special Cell’s Northern Range team.According to the police, Singh was arrested along with an associate, Ajay alias Sandeep, on May 1, 2017, in connection with an FIR registered under Sections 21 and 29 of the NDPS Act at the Special Cell police station. The police had recovered 4 kg of heroin from their possession. Another accused, Buta Singh, was arrested subsequently.During the trial, Darbara Singh was granted interim bail but failed to surrender after its expiry. On October 31, 2018, a court declared him a proclaimed offender. He subsequently left his village and began changing his hideouts to evade arrest.Police said surveillance and source-based inputs revealed that the accused had assumed the identity of “Darwara Ram” to conceal his whereabouts. He had reportedly stayed in Madhya Pradesh and Rajasthan before shifting to Phagwara in Punjab. He was eventually traced and apprehended in Patiala.During interrogation, the accused allegedly disclosed that he had been involved in the narcotics trade for nearly three decades, having entered the business in 1996 after being recruited by a Punjab-based drug supplier, Dayal Singh, as a carrier.The police said he was first arrested in 1997 along with seven others by the Mahalpur police in Hoshiarpur district, with 3 tonnes of poppy straw allegedly recovered from them. In 1998, he was arrested again along with four others by the Phillaur police in Jalandhar district in a case involving 1,600 kg of poppy straw. In 2008, he was arrested by the Salem Tabri police for allegedly possessing 680 kg of poppy straw.He was convicted in all three cases, the police said. While serving his sentence, he was released on parole but absconded. During this period, he came in contact with Buta Singh and allegedly shifted to heroin trafficking. He also became a consumer of the drug, according to the police.A truck driver and helper by profession, Darbara Singh rarely visited his family as he remained on the run and frequently moved between Madhya Pradesh, Rajasthan, Haryana and Punjab to avoid arrest.Further investigation is under way.