TIRUCHY: A grandfather-grandson duo were killed after a lorry hit their two wheeler in Karur on Monday. Venkatachalam (80) and his grandson S Karthik (14) were killed when the moped they were travelling on was hit by a truck at Pethankottai. The lorry bound from Krishnagiri to Thoothukudi hit their two-wheeler, throwing them off the vehicle. While Venkatachalam died on the spot due to heavy blood loss, Karthik was struggling for his life. Onlookers rushed Karthik to Aravakurichi Government Hospital. However, he succumbed to injuries. The police arrested the lorry driver Prabhu (35) from Pochampalli in Krishnagiri. Further investigations are on.