Pakistan's government officials said the earthquake emanated from a remote part of Pakistan's southwestern Baluchistan province which borders Iran and Afghanistan. It measured approximately 7.4 on the Richter scale, the international yardstick to measure earthquakes, and was powerful enough that its tremors were felt as far as Dubai in the Middle East.
The earthquake's intensity was just below that of another earthquake measuring 7.6 that struck parts of northern Pakistan in 2005 and killed more than 70,000 people. Early reports suggest that the extent of damage to property and human casualties may have been limited, as the earthquake's epicenter was near Dalbandin, a remote and sparsely populated town in the western Baluchistan province.
Government officials warned Pakistan will live with the danger of possible aftershocks in coming days. In some instances such aftershocks have come within a week of previous earthquakes.
In Karachi, Saeeda Jehan, a middle aged woman and mother of six children, quietly read religious verses from an Islamic prayer book she carried as she waited for the building with her apartment to be declared safe for her return.
"I was watching TV when suddenly the TV screen began shaking. Then I realized it was a very strong earthquake," Jehan told CBS News while standing in a crowd at Karachi's Stargate neighborhood near the city's main airport.
Forced to leave her apartment after the earthquake, which shook the country around 1:26 a.m. local time, Jehan recounted her ordeal. "Everyone said doomsday has arrived. But I was concerned about my children. It took me 10 minutes to wake them all up before we could all step out."
Jameel Harris, an ambulance driver in Karachi, also forced to leave his flat with his five children and his wife, said there were no reports of heavy damage, though signs of panic were all around. "I have heard of cracks in some buildings but that is not across the board. The damage seems to have been done mostly to older buildings," he said.
In Pakistan's capital Islamabad a western diplomat warned that further damage from the earthquake, notably any of its aftershocks, could seriously undermine Pakistan's future, right at a time when the U.S. is urging the country to extend more cooperation in its campaign to fight militants.
"A humanitarian crisis in Pakistan caused by the earthquake will only undermine U.S. interests," the western diplomat told CBS News on condition of anonymity. "As it is, we must all worry about instability in a country armed with nuclear weapons and with political and economic problems," he added.
Tuesday's earthquake was a powerful reminder of the 2005 earthquake when the death toll of more than 70,000 turned it in to one of the world's biggest humanitarian tragedies.