Local media said the carrier last Friday threatened to call police after the passengers, whose flight was delayed, requested arrangements for their stay.

The flight from Frankfurt to Lagos, which was meant to arrive at the Murtala Muhammed International Airport, was reportedly delayed after diverting to Cotonou in Benin, and Malabo, Equatorial Guinea.

Lufthansa apologised for the flight delay in a circular sent to its passengers last Friday.

The passengers alleged the Lagos airport was not closed, contrary to the claim by the Lufthansa pilot.

Sam Adurogboye, the NCAA public affairs official, on Thursday said the regulator has begun investigation into the matter after receiving complaints from the passengers.

A spokesman for the airline has told the BBC that they are investigating the circumstances of the incident.