Delhi Chief Minister Arvind Kejriwal was slapped by a man during a roadshow in Moti Nagar in New Delhi constituency.
Police said the man has been taken into the custody and an investigation into the matter is underway.
Kejriwal was atop an open jeep when a man wearing a red t-shirt jumped onto the vehicle and slapped the chief minister.
DCP (West) Monika Bhardwaj said the man has been identified as Suresh, 33, and he deals in spare parts in Kailash Park.