At least 348 people were killed and more than 500 injured after a powerful 7.7-magnitude earthquake hit southwestern Pakistan Tuesday, according to local officials.
The provincial government has declared an emergency in Awaran district of Balochistan province, the area worst hit by the quake, which struck at 4:29 p.m. local time at a depth of more than 9 miles.
"At least 200 people have been evacuated," Al Jazeera's Kamal Hyder reported from Awaran.
Brigadier Syed Wajid Raza, the Earthquake Reconstruction and Rehabilitation Authority's chief of staff, told Al Jazeera that many people were still trapped under the rubble of collapsed buildings.
The Pakistani military, meanwhile, has said it has commenced rescue operations in the area.
Abdul Qadoos, deputy speaker of the Balochistan provincial assembly, told Reuters that at least 30 percent of the houses in the impoverished district had caved in.
The U.S. Geological Survey originally measured the earthquake at a magnitude of 7.4 and a depth of 18 miles, but later revised that figure. Pakistan's meteorological office said the magnitude was 7.7.
Tremors were felt across the province as well as in the port city of Karachi, residents have said. Mild tremors were felt as far away as the Indian capital, New Delhi.
The earthquake was so powerful that it caused the seabed to rise and create a small, mountainlike island about 600 miles off Pakistan's Gwadar coastline in the Arabian Sea.
Television channels showed images of a stretch of rocky terrain rising above sea level, with a crowd of bewildered people gathering on the shore to witness the rare phenomenon.
The quake's epicenter was in a remote, thinly populated mountainous area of Balochistan with no major industrial installations.
Muhammad Riaz, a senior Pakistani meteorologist, told local media that the earthquake was "major" and that "heavy destruction" was likely.
Mumtaz Baloch, a senior local administration official in Awaran district, 217 miles southwest of the provincial capital, Quetta, told Agence France-Presse, "There are reports of houses being collapsed in the district due to earthquake.
"We also have initial information about injuries to people as a result of the collapse of houses, but there are no reports of any deaths," Baloch said. "We have dispatched our teams to the affected area to ascertain the losses."
The army deployed helicopters and hundreds of soldiers to help deal with the rescue effort in the huge, earthquake-prone province of deserts and rugged mountains bordering Iran and Afghanistan.
In April, a 7.8-magnitude quake centered in southeast Iran, close to the border with Balochistan, killed 41 people and affected more than 12,000 on the Pakistani side of the border.
Al Jazeera and wire services