Yadav, the AAP candidate in the Lok Sabha election in Gurgaon in Haryana, was taken aback.
"I was talking to you when this person came from behind and put ink on my face," he told journalists. "I did not see him."
He added: "When you take on powerful forces in this country, one must be ready to pay a price. May God forgive this man (attacker)."
The arrested person has told police that his name is Sagar Bhandari and he is a resident of Assam.
