Four foreign oil workers kidnapped off Nigeria freed
"We can confirm that our four kidnapped crew were released last night and that they are OK," Sea Trucks spokeswoman Corrie van Kessel said in an email.
Piracy and kidnapping in the Niger Delta and offshore are common, and West Africa's oil-rich Gulf of Guinea is second only to the waters off Somalia for the risk of pirate attacks, which drives up shipping insurance costs.
(Reporting by Joe Brock; Editing by Alison Birrane)