It was found in the luggage of two men who arrived from India and Sri Lanka.
The incumbent should admit failure and resign, the opposition leader said.
The Transport Authority also announced fixed rates.
Adeeb has not been allowed to disembark.
Police said efforts are underway to bring Adeeb back.
The programme kicks off in Addu City on Friday.
They included "a high-profile drug trafficker."
Meridiam owed STO for fuel released on credit in 2010.
Probes are ongoing into complaints against several top judges.
The witness implicated the six defendants during anonymised testimony.
It was the first case wrapped up by the inquiry commission.