At least three people were electrocuted and nearly 20 injured in Bihar's Patna district on Thursday night when an overhead high voltage wire fell on the roof of a running train, where dozens of passengers were sitting, police said.The incident took place near the Nima halt on Patna-Gaya rail route of Danapur railway division of East Central Railway."Three passengers, sitting on the train roof, died on the spot after an overhead high voltage wire fell on them," a district police official said.All the injured were admitted to the Patna Medical College and Hospital for treatment.According to police officials, hundreds of passengers and local residents protested against this incident.In Bihar, people commonly travel on train roofs despite the risk to their lives.