A bus crammed with pilgrims coming back from a religious festival crashed in southwest Pakistan on Friday killing at least 20 and leaving 10 others critically injured, officials and a hospital doctor said.

The bus careened off the road into a ditch during the early morning in the Karkh area of Khuzdar district, in Pakistan’s southwestern province of Balochistan.

“The bus was overloaded, and passengers were even traveling on the roof of the bus,” a Pakistani security official in the area told Reuters after paramilitary forces and soldiers were sent to help the survivors.

“We have received 20 bodies and over 40 injured in Khuzdar district hospital,” Dr. Manzoor Zahir told Reuters, adding that the condition of at least 10 of the injured was serious and the death toll could increase.

Traffic and rail accidents are commonplace in Pakistan, partly because of the poor state of roads and track.

At least 56 people were killed on Monday when a passenger train smashed into the derailed carriages of another train in southern Pakistan.