At least 53 people died Thursday morning in one of the worst traffic accidents in the history of the southern African nation of Zambia.

According to reports, a bus operated by the postal service, but also carrying many ordinary passengers, collided head- on with a semi-truck and another sport utility vehicle, causing dozens of deaths and several injuries, near the town of Chilbombo, in the center of the country.

The postal truck, carrying 74 passengers, was moving on a two-lane highway toward the capital of Lusaka, about 60 miles to the south.

The Associated Press reported that police investigators had not determined the cause of the crash even hours after it occurred. The final death toll could rise as bodies remain trapped inside the wreckage of the mangled vehicles.

But Harry Kalaba, an official in the vice president's office, told Agence France-Presse that all three vehicles were speeding.

The highway where the smashup happened reportedly carries very heavy traffic, even at night.

Zambian President Michael Sata expressed his condolences to the families of the victims.

“Allow me on behalf of my Cabinet, the first lady and indeed on my own behalf to convey my deepest condolences to the bereaved families,” Sata said.

“We pray that the Lord Almighty grants the bereaved families comfort and strength during this very painful period.”

This is hardly the first time Zambia has witnessed such carnage on its highways.

In 2005, 44 people were killed when a truck filled with high school students slipped off a mountain road in the north of the country.

The BBC reported that Zambian vehicles are often poorly maintained and overcrowded.

According to the Zambian police, traffic fatalities have been increasing for the past decade, currently exceeding 1,200 annually (about half of them pedestrians, including many children).

The World Health Organization said that 37.94 out of 100,000 people in Zambia died in highway and road accidents in 2011, making it the world’s eleventh most dangerous country with respect to traffic fatalities.

The Times of Zambia reported last month that traffic accidents are now the third leading cause of death in the country, behind only HIV/AIDS and malaria.

In an op-ed piece in the paper, the Times wrote: “This is a sad state of affairs which requires a steadfast approach through a neatly-prepared blueprint. Accidents have continued to claim valuable lives and rich human resource which could be utilized in the country’s growth agenda. It has proved to be one of the major barriers to economic and social growth.”

The Times partially blamed the poor condition of the roads, but also attributed the deaths to badly maintained vehicles that shouldn’t be allowed on the roads, as well as careless and inattentive drivers, particularly those who operate minibuses and taxis.

“Motorists must follow rules to avoid road carnage,” the column concluded.

The country’s Road Transport and Safety Agency reported that the number of traffic accidents in Zambia surged by 49 percent between 2010 and 2011, partly due to the spike in the number of registered motor vehicles. In 2011 alone, more than 52,000 cars and trucks were imported into Zambia, raising the total number to more than 380,000.

At particular risk from these road tragedies are children.

“Road traffic crashes are the leading cause of death among people aged between 10 and 24 years old,” the agency stated.

“In Zambia, road traffic injuries have become one of the significant causes of childhood morbidity and mortality. The bulk of the crashes amongst these children are predictable and preventable. Many involve children playing on the streets, young pedestrians, cyclists, novice drivers and passengers of public service vehicles.”