In recent months, the GNIB
established Operation Hotel to probe the extent of trafficking of women for sexual exploitation in Ireland.
checked the dead man's fingerprints against the non-national database on Friday, but are still awaiting a perfect match.
He said he was disturbed that the GNIB
could not be contacted on the day.
Operation Hyphen led to more than 40 arrests over a two-day period last summer and the GNIB
are now cracking down on bogus English language schools which are issuing students, mainly from China, with false attendance records.
source said the reason behind the large gardai presence on board the craft was to ensure a safe flight to Nigeria.
The GNIB came into force in May 2000 and is responsible for all Garda immigration operations.
Last July more than 200 GNIB officers raided 100 houses in Dublin.
Since September last year the Immigration Unit at Dublin Airport has been part of the GNIB.
officer said: "We believe many Irish women are being paid to enter arranged marriages with non- nationals without knowing the full consequences, such as the loss of their social welfare benefits.