San Francisco/New Delhi, Aug 1 : Mobility startup Bolt Mobility, co-founded by eight-time Olympic gold medalist Usain Bolt, has abruptly disappeared from several of its markets in the US, leaving e-bikes and equipment abandoned amid unanswered calls, the media reported. Bolt had raised $40.2 million, along with an undisclosed investment from Chennai-based Ram Charan Company in India in May this year. According to a TechCrunch report, Bolt Mobility stopped operating in at least five US cities, including Portland, Oregon, Burlington, South Burlington and Winooski in Vermont and Richmond, California. "City representatives said they were unable to reach anyone at Bolt, including its CEO Ignacio Tzoumas," the report said late on Sunday. Portland suspended Bolt's permit to operate there last month after the company failed to "provide the city with updated insurance and pay some outstanding fees". "All of our contacts at Bolt, including their CEO, have gone radio silent and have not replied to our emails," Robert Goulding, public information manager at Burlington's Department of Public Works, was quoted as saying. Bolt had a presence in more than 50 markets across the US. The investment from Ram Charan Company in May was set to be used to propel transportation sustainability efforts by bringing cutting-edge solid state battery technology; energy-efficient, metal-like plastics made from recycled waste; and coiless electric motors to small and personal vehicles. "Our partnership with Bolt Mobility, a brand with high standards in performance and sustainability, is an important step forward for Ram Charan and its group companies," Kaushik Palicha, Director, Ram Charan, had said in a statement. "We will support Bolt's vision of ensuring sustainability throughout their entire value chain, from quality of energy, quality of materials, and the reach of their mobility devices," Palicha had said. "I look forward to partnering with Ram Charan as we help usher in Transportation 2.0," said Bolt CEO Tzoumas. "Together, we are helping create healthier, more livable cities of the future.a" Bolt's social media has now gone silent, and hasn't posted on Instagram since June 11 or on Twitter since June 2. /IANS