A man injured by the earthquake is attended to by family at a hospital in Quetta, Pakistan. Photograph: Arshad Butt/AP

A powerful earthquake has killed at least 135 people and destroyed hundreds of homes in south-western Pakistan, officials said.

The death toll was expected to rise from the quake, which measured at magnitude 6.4, as reports arrived from remote areas of the affected province of Baluchistan, which borders Afghanistan.

The worst-hit area appeared to be Ziarat, where hundreds of mostly mud and timber houses were destroyed in five villages, according to the local mayor, Dilawar Kakar. Some homes were buried in a landslide triggered by the quake.

"There is great destruction. Not a single house is intact. This time the [death toll] we have got is 135. It may be more," Kakar told Express News television.

He said hundreds of people were injured and about 15,000 made homeless. Ziarat, a scenic valley, is one of Baluchistan's tourist spots.

"I would like to appeal to the whole world for help. We need food, we need medicine. People need warm clothes, blankets because it is cold here," Kakar said.

In the village of Sohi, an Associated Press reporter said he saw the bodies of 17 people killed in one collapsed house and 12 from another. Distraught residents were digging a mass grave to bury them.

"We can't dig separate graves for each of them, as the number of deaths is high and still people are searching in the rubble," said Shamsullah Khan, a village elder.

Other survivors sat stunned in the open with little more than the clothes in which they had been sleeping. In nearby Kawas, dozens of dead and injured were brought to a hospital in Kawas in Ziarat district. A doctor, Mohammed Irfan, said the hospital was unable to cope.

With roads blocked by landslides, officials said the army was ferrying troops and medical teams on four helicopters to villages in the quake zone and airlifting a field hospital as well as thousands of tents and blankets to the area.

The quake struck two hours before dawn and had a preliminary
magnitude of 6.4, the US Geological Survey reported. It originated 10 miles (15km) below the Earth's surface.

It is the region's deadliest quake since one measuring magnitude 7.6 devastated Kashmir and northern Pakistan in October 2005, killing about 80,000 people and leaving hundreds of thousands homeless. Officials said the area affected today, 400 miles from the capital, Islamabad, was much less densely populated.