At least 18 people were killed in a road accident on Monday morning when a trailer ran into a bus that had stopped to change a punctured tyre on the National Highway near Hala, rescuers said.

The victims, residents of Hyderabad, were returning from Sakrand, where they had gone to attend a wedding. On their way back home, the driver had stopped the bus to change the tyre when a trailer rammed into the stationary vehicle.

According to Edhi rescue teams, which arrived at the scene soon after the accident, around 30 people had been injured, out of which at least six were in critical condition. The injured were shifted to Liaquat University Hospital in Hyderabad.

Cranes are being used to lift the wreck as rescue officials fear that there could be more people trapped underneath it.