Three persons were killed and 18 others injured after a PRTC bus carrying passengers rammed into a flyover near the Chief Minister’s residence in Sangrur on Wednesday.The bus was on its way to Chandigarh from Sangrur when the accident occurred. Of the 18 injured, 15 were referred to Government Rajindra Hospital, Patiala, for treatment.According to eyewitnesses, the bus first rammed into a pole supporting the flyover before hitting a tree as it skidded off the road. Local residents joined the police and district administration in the rescue operation.Punjab Chief Minister Bhagwant Mann expressed grief over the loss of lives in the accident.