When Kejriwal was shaking hands with his supporters, the person punched him on his back and even tried to slap him.
Later the man was thrashed by AAP workers and handed over
"Some people are ready to go to any extent to become Prime Minister. Let them do whatever they are doing. Our religion teaches us non-violence. If we raise our hands, this movement will come to an end," Kejriwal said while blaming BJP for the assault.
Appealing for calm, the AAP leader asked his supporters not to indulge in any violence.
However, soon after the incident, the AAP leader's roadshow ended abruptly after which Kejriwal left for his residence.
Kejriwal was expected to cover areas like Saket, Mehrauli and Lado Sari, but did not do so. Party sources said that the attack on him was one of the reasons for ending the roadshow abruptly.
Kejriwal has been attacked a number of times in the past.
On March 28, he was attacked by a man, who claimed to be a supporter of anti-corruption crusader Anna Hazare, during his election rally in Haryana.
Seeking to garner support for the party's South Delhi candidate Devendar Sehrawat, Kejriwal's convoy started from Govindpuri Metro station and passed through Sangam Vihar and Kalkaji.
He received an over-whelming support by AAP volunteers, who crowded his car. Everywhere he went, his supporters had assembled well in advance with garlands.
"The country has been seeing a miracle for the past one year. A new party was formed and everybody said that we will get 4-5 seats in the Delhi Assembly elections. But we got 28 seats and formed a minority government" he said.
"No government in the country has worked like our 49-day government. We reduced the electricity and water tariffs," he said.
He added that he quit the Chief Minister's post because both the Congress and BJP did not allow the Jan Lokpal Bill to be passed and he did not run away from governance.
"I have not fled to Pakistan. I am here and will fight against corruption till my last breadth," he said.
However, as the convoy reached the Dakshinpur area, supporters again flooded to greet and garland him. In the melee, he was punched by an unidentified man.
"The opposition should not resort to violence. Whatever happened was shameful and the opposition should not resort to such steps," said an AAP worker dejected after the cancellation of the roadshow.
AAP has fielded Sehrawat, a former defence personnel against BJP's Ramesh Bidhuri and Congress MP Sajjan Kumar in South Delhi Lok Sabha constituency.