The man was later identified as Solairaja, a local AIADMK worker and supporter of Mr Panneerselvam, the police said.
As the AIADMK Puratchi Thalaivi Amma leader was being received by his supporters just outside the arrival entrance, the knife kept by Solairaja in his waist fell down. Immediately, some supporters of Mr Panneerselvam mistook it as an attempt to attack their leader and overpowered Solairaja, who is said to be a professional cook, and handed him over to airport police.
During his interrogation, Solairaja told police that he was also a follower of Mr Panneerselvam and did not intend to attack him. He said he always used to keep the knife, police said adding further investigation was on.
He is visiting Tiruchirappalli to meet his supporters.