Faridabad, Nov. 17 -- Investigators tracing the final days of Umar un-Nabi detained the owner of a medical shop in Dhauj who police described as a "friend" of Nabi and one of the last people to speak with him in Faridabad before the suspected suicide bomber moved base to Nuh under an alias. The shop owner, who investigators said had known the 35-year-old doctor for nearly a year, became a key figure on Sunday as teams in Faridabad tried to reconstruct how Nabi slipped out of the city, rented a room in Nuh as officials arrested his associates and unravelled their module. Investigators said that CCTV footage from markets and testimonies from staff at eateries have given them a window into Nabi's final movements in the days leading up to the November 10 blast. According to officials, CCTV footage recovered earlier this week showed Nabi visiting a medical shop in Dhauj, 800 metres from the Al-Falah Medical College where he worked. During that visit on October 29, he left his cellphone to charge and spent nearly half an hour talking to the shop owner. But in other CCTV clips - six in total - from Dhauj market and Sirohi village on October 29, he is seen talking on a phone, appearing tense and repeatedly checking his surroundings as he walked after parking his car by the roadside. Police officials familiar with the case said teams from NIA and Faridabad Police have since questioned owners and workers at three eateries along a 12-km stretch between Hidayat Colony and the Nuh-Alwar Road, where Nabi was a regular visitor between October 30 and November 9. Testimonies from the staff at dhabas along this stretch appeared to suggest he was restless and anxious. To be sure, this would be around the same time that sleuths had cracked down on the terror module. "He used to come alone every night," said Akram Khan, a server at a small roadside dhaba. "He would quietly ask what was cooked for the day. He ate fast, barely spoke, and tipped Rs.100 before leaving." Khan said Nabi appeared tense and restless, glancing constantly at passing vehicles. "He was never relaxed. He ate while looking toward the road, as if expecting someone." Another dhaba worker, Mohammad Zubair, who runs a biryani stall nearby, said he saw Umar twice. "The second time, he seemed agitated, talking on the phone in what sounded like Urdu but with a Kashmiri accent." A fruit vendor nearby said he often saw the Hyundai i20 parked along the Nuh-Alwar road. "After eating, he would sit in the car for several minutes without starting it. One night, I saw him shouting on the phone and banging his hand on the car door. He looked very upset," the vendor said....