City police on Monday arrested the driver of the truck, a day after it hit several vehicles on a Mumbai-Bengaluru highway stretch in Pune and caused a pile-up, while the preliminary investigation suggested the driver had switched off the engine on a bridge slope resulting in the accident, officials said.

Police also arrested the driver's assistant from Pimpri Chinchwad township, an official said. At least 24 vehicles were damaged late Sunday evening when the truck hit multiple vehicles on the downward slope of Navale bridge on the highway in Pune, injuring more than 20 people, eight of them hospitalised, an official had said.