Lagos - An international watchdog says pirates have attacked an oil tanker off Nigeria but failed to board it or harm its crew.
The attack occurred early on Saturday in the Gulf of Guinea off Western Africa, according to the London's-based International Maritime Bureau.
The six pirates chased the tanker and shot at it, slightly damaging the vessel. The watchdog's brief statement did not name the tanker or say where it is based or where it was travelling.
Piracy off Nigeria's oil-rich delta has escalated from low-level armed robberies to hijackings and cargo thefts. Some believe militants involved in fighting in Nigeria's southern delta now take part in the piracy.