A 6.3 magnitude earthquake that struck northern Afghanistan overnight killed more than 20 people and injured around 320, the health ministry said on Monday.

In the Balkh and Samangan provinces "around 320 countrymen have been injured and more than 20 have been killed," ministry spokesman Sharafat Zaman said in a video message shared with journalists, specifying that this was a preliminary toll.

The earthquake destroyed part of the holy shrine of Mazar-i-Sharif, Balkh province spokesperson Haji Zaid said, referring to the Blue Mosque.

The US Geological Survey said the quake's epicentre was located 22km west-southwest of the town of Khulm, and that it struck at 12.59am at a depth of 28km.

In the Afghan capital of Kabul, the Ministry of Defense announced that rescue and emergency aid teams have reached the areas affected by the tremor, and have begun rescue operations, including transporting the injured and assisting affected families.

The United Nations said its teams are on the ground assessing needs and delivering urgent aid.

Monday's earthquake came after a deadly quake stuck eastern Afghanistan in late August, killing more than 2,200 people and injuring thousands more. (Agencies)