Khan is facing an inquiry in a case related to a settlement between the PTI government and a property tycoon, which reportedly caused a loss of 50 billion Pakistani rupees ($17.6 million) to the national exchequer.
Mere hours after Imran Khan's arrest, civil unrest swept across Pakistan, with protesters hitting the streets in Lahore, Islamabad, Peshawar and other cities.
What is going on? Sputnik explains.