Six people were killed and 12 others suffered injuries in a collision involving six cars on the National Highway due to heavy fog and smog in Thatta district of the southern Sindh province, police in the area told Xinhua.

Separately, a passenger bus traveling from eastern Punjab's Multan district to Rawalpindi rammed into a trailer stopping on the road in Bhakkar district due to smog, causing two deaths and 10 injuries, according to police in the district.

Motorway police have urged people to limit unnecessary travel and drive carefully amid bad weather conditions, Xinhua news agency reported.