Ringed with snipers and sandbag bunkers, the makeshift office of a Kabul academic spearheading President Ashraf Ghani's unprecedented anti-corruption drive could be mistaken for a military garrison.

Handpicked by Ghani to oversee his anti-graft campaign is Hamidullah Farooqi, a Kabul University economics lecturer who was part of the president's election campaign.

"I used to live an ordinary life driving an ordinary Toyota," said Farooqi, 62, reading glasses perched on his forehead. "But investigating corruption means investigating people with dangerous connections. It's like fighting the mafia - the economic mafia."