The earthquake struck in Afghanistan, close to its border with Tajikistan, at 10:28 GMT, according to the US Geological Survey (USGS).
There are reports the tremor was felt in Kabul, Islamabad, Lahore and Delhi, forcing residents to leave their homes.
In October 2015, a magnitude-7.5 quake in the same border area killed close to 300 people.
Mild tremors were felt in Delhi, other parts of north India after a moderate intensity earthquake hit Hindu Kush region in Afghanistan today. The rector scale reads 6.8 points.