A supply ship has been hijacked and then released in the Niger Delta in a brief incident on Monday.
The IMB said the unnamed vessel was targeted off Nigeria while underway.
It added that all 17 crew were released by Monday evening, and the ship was freed.
It was not clear whether a ransom had been paid.
A 2009 amnesty deal for militants in Nigeria's oil-producing delta region led to a sharp decline in attacks on the oil industry, though sporadic incidents continue to occur.
