Four killed in explosion at mosque in Mazar-e-Sharif, Afghanistan

"At least four people were killed and six were injured in an explosion at a mosque in the northern city of Mazar-i-Sharif," the Twitter post said.

Earlier in Kabul, an explosion occurred at a currency exchange office, as a result of which at least 20 people were injured.

The cause of the incident was a grenade thrown at people.