The Nigerians, identified as Mark and Henry, were held following a tip-off by one of their accomplices.
According to media reports, the accomplices were arrested on October 30 with cocaine and ecstasy tablets.
The two Nigerians were suppliers of high-end drugs, the police said in a report published on republicworld.com.
Six mobile phones have been seized from them, the police said.
While Mark has two passports, Henry has none, they said, adding that further investigations have begun.