Lagos - London-Based oil exploration firm Afren said on Monday that Nigerian gunmen had attacked its offshore oil rig and abducted five crew members.
The company also said two others were injured in the attack which occurred on Sunday.
In a statement released on Monday, the company said two crew members are stable after receiving wounds to the leg, and have been evacuated by helicopter to a shore-based clinic.
It is believed that five crew members had been taken hostage, the statement added.
"A security breach has occurred on the High Island VII jackup rig, which had recently arrived on location, preparing to commence infill drilling at the Okoro field," the company said.
"A second security breach occurred at the AT 101 support vessel. Together with our indigenous partner AMNI International, we are working with the relevant authorities and the vessel and rig are both under the control of the Company. Drilling operations on the rig are temporarily suspended. An update will be provided in due course," the statement said.
Over 300 foreigners have been seized in the Niger Delta since 2006. Almost all have been released unharmed after paying a ransom.