An unidentified man slapped Congress leader Hardik Patel on Friday while he was addressing a gathering at the Jan Akrosh Sabha here.
Hardik was in the middle of his speech here when the attacker got on to the stage and slapped him.
A scuffle broke out after the incident between the supporters of the Congress leader and the attacker.
This incident comes a day after a shoe was hurled at BJP's national spokesperson GVL Narasimha Rao while he was addressing a media briefing in New Delhi.
He, however, had a narrow escape as the shoe did not hit him.
Patel emerged as the leader of the Patidar agitation demanding reservation for the community in Gujarat in 2015. The people from this community were considered to be bedrock supporters of the BJP.
On March 12, Patel officially joined Congress in Ahmedabad in the presence of party chief Rahul Gandhi and senior leader Mallikarjun Kharge.
Prior to joining Congress, Hardik had said he would help strengthen the ideology of the party and take it to the villages.
Gujarat will go to polls on April 23 for the 26 Lok Sabha seats at stake. Counting of votes will take place on May 23.