Islamabad, Pakistan (CNN) -- An earthquake in Pakistan, powerful enough to prompt the appearance of a small island off the coast, has killed more than 200 people, Pakistani officials said.

The 7.7-magnitude quake struck in a remote area of southwestern Pakistan on Tuesday, but it had severe consequences.

At least 208 people were killed in the district of Awaran and the city of Turbut in Balochistan province, Asad Gilani, the provincial home secretary, said Wednesday.

In addition to the fatalities, around 350 people have been injured, he said, and more people are still trapped in rubble.

The quake was strong enough to cause a mass 20 to 30 feet high to emerge from the Arabian Sea like a small mountain island off the coast of Gwadar, local police official Mozzam Jah said. A large number of people gathered to view the newly formed island, he said.

Large quakes can cause significant deformation to the earth's crust, particularly visible along coastlines.

The island is about 100 feet in diameter and about one mile off the coast, GEO TV reported.

Zahid Rafi, principal seismologist for the National Seismic Monitoring Center, confirmed the island had formed. He said it was "not surprising," considering the magnitude of the earthquake.

But John Bellini, a geophysicist with the U.S. Geological Survey, said that generally it would be unlikely for such a large island to emerge from a quake like Tuesday's.

Many things, such as the tide, could come into play regarding the rise of the island, he said.

More than 1,000 troops will be sent to the area to provide aid, including rescue teams and medical teams, Maj. Gen. Asim Bajwa said.

With a depth of about nine miles (about 15 kilometers), the quake struck 43 miles (69 kilometers) northeast of Awaran and 71 miles (114 kilometers) northwest of Bela, the U.S. Geological Survey said.

Some mud-walled homes fell in Awaran, said Latif Kakar, director of the Provincial Disaster Management Authority in Balochistan.

The tremors lasted two minutes. People flocked out onto the streets of Quetta, the provincial capital.

Aftershocks could be felt in Karachi, hundreds of miles to the southeast.

CNN's Mari Ramos and Elizabeth Joseph, and journalist Sophia Saifi contributed to this report.