ISLAMABAD, Pakistan (CNN) -- Rescuers dug through the rubble left by a 6.4-magnitude earthquake that struck a remote area of southwest Pakistan Wednesday, killing at least 160 people and leaving thousands homeless on the brink of winter, a humanitarian group spokesman said.
Quake victims tend to an injured man in southwestern Pakistan.
"We can confirm that there are 160 reported dead, 500 injured and around 10,000 population displaced in and around the area of Ziarat," said Asar Ul Haq, senior disaster manager of the International Federation for the Red Crescent delegation in Pakistan.
The death toll was expected to rise as rescue workers dug through the rubble of mud homes in a remote part of Baluchistan province, said the province's Deputy Director of Public Safety Mohammad Ali.
"There are still searching. There are some villages completely destroyed. There is a lot of destruction," Ali said. Watch images of the damage »
The quake struck before daybreak, about 60 kilometers (35 miles) north-northeast of the province's capital, Quetta.
Another quake measuring maginitude 6.2 struck southwest Pakistan Wednesday, hours after the initial jolt, according to the U.S. Geological Survey.
The worst-hit area appeared to be the district of Ziarat, where a quake-induced landslide buried dozens of houses.
Ali put the death toll at 150 and rising. Thousands of others were homeless, he said.
Ten hours after the quake, the rescue operations continued with the Pakistani army sending helicopters to ferry in blankets and relief supplies and airlift the scores of wounded. Watch a report on the deadly quake »
TV images from the scene showed women squatting next to gaping craters where houses once stood -- their heads buried in their hands.
Villagers clawed through heaps of dirt and debris searching for signs of life. Elsewhere, solemn residents shoveled dirt to create mass graves to bury the dead.
Balochistan, located near the Afghan border, is the largest province in Pakistan but one of its least populated. A magnitude 7.5 quake in the province's capital, Quetta, killed 30,000 people in 1935, according to the United States Geological Survey.
The deadliest quake in Pakistan, however, occurred in October 2005 when a magnitude 7.6 earthquake killed 86,000 people in the northern part of the country, the USGS said.
While rich in natural resources, Balochistan is also battling an insurgency.
Militants there have for years complained that the central government has paid little attention to them and their economic needs. They have been fighting Pakistani military forces for self-rule.
More recently, the province has seen an influx of Afghan refugees. And the Afghan government believes that key Taliban leaders may be hiding among them.
Pakistan has said the militants in Balochistan do not have links to the Islamic hard-liners who have launched assaults in other parts of the country
CNN's Saeed Ahmed in Atlanta and Zein Basravi in Islamabad contributed to this report