At least 160 people were killed when a powerful earthquake struck southwest Pakistan on October 29, bringing down mud-walled houses. Officials say they expect the death toll to rise as some villages remain cut off.

The U.S. Geological Survey said a 6.4 magnitude quake hit 60 km (40 miles) northeast of the city of Quetta before dawn.

The Pakistan Meteorological Department put the magnitude at 6.5 and said the quake struck at 5.10 a.m. (2310 GMT).

The epicentre was near the scenic valley of Ziarat, one of the main tourist spots in Baluchistan province.

Officials in the hilly Ziarat district, 70 km (45 miles) northeast of the provincial capital, Quetta, said many houses had collapsed and some had been destroyed in landslides trigged by the quake.

Officials and hospital staff said scores of people had been injured, most when mud walls collapsed or in the panic when people rushed from their homes.

Quetta was largely destroyed in a severe earthquake in 1935 which killed about 30,000 people.

The region's worst earthquake was in October 2005 when about 75,000 people were killed, most of them in mountainous northern Pakistan, in a 7.6 magnitude quake.

Large parts of south Asia are seismically active because a plate known as the Indian plate is pushing north into the Eurasian plate.

Baluchistan is Pakistan's largest province but one of its poorest and most thinly populated.

It has the country's biggest reserves of natural gas but there were no reports of damage to gas facilities.