Authorities in Pakistan say earthquake relief efforts are being hampered by the remoteness of the mountainous quake zone.
Officials say at least 327 people were killed after thousands of mud homes collapsed in the mountainous Awaran district of Baluchistan province.
Hundreds of other people have been injured and displaced.
Most of the damage has occurred in the country’s impoverished Baluchistan province, where the epicenter of the 7.7 magnitude quake was located.
The remoteness of the mountainous quake zone has prevented authorities from determining the extent of the devastation more than 24 hours after the calamity struck.
Muhammad Saeed Aleem, head of Pakistan's National Disaster Management Authority, told reporters Wednesday that arrangements are being made to send food, tents and blankets to the affected areas. He says satellite images are being gathered to assess the damage and he feared the human losses are likely to increase.
"It was a massive earthquake and apparently there are huge losses, but the government will be able to discuss it once satellite images of the area are gathered," said Aleem.
Rescue workers say that houses, mostly made of mud, in the worst-hit district of Awaran and surrounding areas have been flattened, causing most of the deaths. The tremor also disrupted road links which is hampering relief activity.
United Nations officials say they are standing by to provide support if requested but so far Pakistan's government is leading the response.
Dan Teng’o, a spokesman of the U.N. office for the Coordination of Humanitarian Affairs in Pakistan, says it is in contact with the provincial government and has received initial reports of the losses the quake has caused.
“It has indicated that 80 percent of the houses in Awaran district, which is the most affected district, 80 percent houses there have collapsed and it could be more because they have not been able to access some of the remote areas," said Teng’o.
Hundreds of Pakistani troops and paramilitary soldiers as well as military helicopters carrying emergency supplies have arrived in the region to help evacuate the thousands of people injured and made homeless.
The resource-rich, sparsely populated Baluchistan region borders Iran and Afghanistan and has been in the grip of a low-level separatist insurgency for years. Ethnic Baluch insurgents frequently attack government officials and installations.
Pakistani officials say the massive earthquake that struck the remote district of Awaran in Baluchistan province was strong enough force to create a small island visible off the southern coast, Sept. 25, 2013.
Villagers look for belongings amid the rubble of their destroyed homes following an earthquake in the remote district of Awaran, Baluchistan province, Pakistan, Sept. 25, 2013.
Army troops leave Karachi, Pakistan heading for an earthquake-affected area in the Baluchistan province, Sept. 25, 2013.
Survivors collect their belongings near the rubble of a mud house after it collapsed following an earthquake in the town of Awaran, southwestern Pakistani province of Baluchistan, Sept. 25, 2013.
Earthquake survivors from the town of Awaran, in southwestern Pakistani province of Baluchistan, receive first aid at the Civil Hospital in Karachi, Sept. 25, 2013.
The rubble of houses are seen after they collapsed following an earthquake in the town of Awaran, southwestern Pakistani province of Baluchistan, Sept. 25, 2013.
A survivor of an earthquake sits as he takes tea on the rubble of a mud house after it collapsed following the quake in the town of Awaran, Baluchistan, Sept. 25, 2013.
People rush out of their offices after they felt a major earthquake that struck Baluchistan province in southwest Pakistan, Sept. 24, 2013.