Airport sources said the arrested Mohammed Azarudin, who arrived by a Thai Airways flight, told the Customs officials that one of his friends in Thaliand gave the suitcase to him with a request to handover it to a person in Chennai.
He said he was given Rs 10,000 for carrying the suitcase and was unaware of the contents in it.
Customs officials were investigating how Azaruddin managed to board the flight from Thailand clearing security checks.
The suitcase was later handed over to Forest Department, the sources said.