Bharti Ahirwar (35), Vishaka Ahirwar (11) and Laxmi Ahirwar (1) died on the spot when the trolley overturned on National Highway 26 under Bhandri police station area, Sagar Additional Superintendent of Police (ASP) Pankaj Pandey said.
He said the injured mostly in critical condition have been admitted to the district hospital.
Pandey said the victims were on their way to Malthon area to attend a religious function when they met with the mishap.