Arvind Kejriwal was atop an open jeep when a man wearing a red T-shirt slapped him.
The man who slapped Delhi Chief Minister Arvind Kejriwal during a roadshow in the national capital last week has said he "regretted" the act.
"I do not know why and how it happened that day. When I was behind bars; I regretted what I did that day," said Suresh, who was arrested on Sunday, news agency ANI reported.
According to the police, Suresh said he slapped Mr Kejriwal because he was dissatisfied with the behaviour of Aam Aadmi Party leaders. The 33-year-old clarified that he is not associated with any political party.
"I am not affiliated with any political party. Nobody asked me to do this. Police did not misbehave with me. They only said what I did was wrong," he added.
Mr Kejriwal was atop an open SUV when Suresh jumped on to the bonnet and slapped the Chief Minister before being overpowered by AAP volunteers.
This was not the first time the Aam Aadmi Party chief was assaulted.
Mr Kejriwal was slapped by a man in 2015 while campaigning for the Delhi assembly elections. The same year, an autorickshaw driver slapped him during a roadshow in the city. In November last year, a man smeared chilli powder on Mr Kejriwal's face inside the high-security Delhi Secretariat.