Having worked as a driver for a sub-divisional magistrate (SDM) till a couple of months ago, a 47-year-old taxi stand owner impersonated the officer to extort from a trucker in the west Delhi’s Dwarka, the Delhi Police said on Monday, after arresting him and his three associates.The four men were arrested in the early hours of Friday after they gave chase to a cement-laden truck from Gurugram to Dwarka before compelling the driver to unload 19 sacks of cement, Anto Alphonse, deputy commissioner of police (Dwarka), said. During his days as the SDM’s driver, the alleged mastermind, identified as Satyawan, had learnt the officer’s mannerism and understood his duties that involved conducting raids, the DCP said. Once his 18-month contract with the SDM ended last May, Satyawan was careful not to remove two stickers — saying ‘SDM’ and ‘Govt of Delhi’ — from the two cars he had leased out to the officer. The crime which led to the bust of the alleged extortionist gang unfolded on the intervening night of Thursday and Friday. The DCP said the four suspects were travelling in two cars, a Wagon R and a Swift Dzire.“They had set their eyes on a truck loaded with 200 sacks of cement. They followed the truck from Gurugram to Bamnoli village in Dwarka before intercepting the vehicle. Accusing the truck driver of overloading his truck, they posed as an SDM and his driver and threatened to challan him,” said the DCP.The truck driver was allegedly told he would be allowed to go scot-free if he offloaded a few sacks from the vehicle. “The truck driver was too afraid to resist the extortion and unloaded 19 sacks from his truck,” said the DCP.The trucker drove away even as Satywan allegedly called his associates who were waiting nearby in a Swift Dzire. They then began loading the cement-filled sacks in the Swift Dzire.The trucker had barely driven for a few hundred metres when he spotted a police vehicle that was out on patrolling duty. “Already suspicious about the raid, the driver narrated the entire story to the police team,” said the DCP.The police team drove towards the crime spot to find the Wagon R at the same place, but the Swift Dzire being driven away. “We caught Satyawan and his driver, Dalip Singh, from the spot and seized their Wagon R,” said the DCP.The police team then alerted another emergency response vehicle (ERV) about the fleeing Swift Dzire. “Since the sedan was overloaded with cement sacks, it wasn’t able to speed away and we caught up with them,” said the officer.The other two arrested men were identified as Devender and Pankaj. Police said that Devender and Pankaj were sons of the other arrested man, Dalip Singh. “The father and his two sons were unemployed and had decided to accompany Satyawan for the extortion,” said police.