Two speeding tour buses collided head-on on a southern Afghan highway Monday evening, killing about 40 people on board, a highway police commander said.

The crash killed about 15 women and children, along with 25 men, said Jalali Khan, the Zabul province highway commander. It occurred on Afghanistan's main Kabul-Kandahar highway near the border area between Ghazni and Zabul provinces, he said.

"There's no speed limit for these buses, and they wanted to reach their destinations as soon as possible," Khan said. "They're careless drivers, and someone made a mistake. Around 40 people died because of these careless drivers."

Both drivers died, Khan said.

Few police patrol Afghanistan's highways and there are almost no speed limits. Police checkpoints are set up along the highway but are there to provide security from Taliban militants or to search for weapons or drug smugglers - not to enforce basic traffic safety laws.

The crash occurred around 5 p.m., an hour before sundown, when Afghans in this Muslim country would be allowed to eat and drink for the first time since before sunrise. Muslims observing the holy month of Ramadan do not eat or drink during the day during the religious period.