Before the kidnapping of two American mariners off the coast of Nigeria early Thursday, piracy in the region had become such a "widespread and violent" practice in recent months that the industry issued a stark warning to anyone operating in the dangerous waters -- and told them what to do if pirates take over the ship.
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Two Americans, Captain and Chief Engineer aboard the oil supply vessel C-Retriever, were taken from the vessel after being separated from the other crew members by their nationality, a Pentagon official told ABC News Thursday.
A spokesperson for the Nigerian Navy said his military has undertaken a search and rescue mission for the Americans, but there has been little news since word of the attack spread. It is unclear where exactly the Americans are now, but the Nigerian Navy spokesperson said they are thought to be held off the Nigerian coast.
Security experts told ABC News the FBI, which is leading the investigation into the kidnapping, is working to get in contact with the kidnappers -- a process that former FBI special agent Brad Garrett, an ABC News consultant, said could take days, depending on whether the FBI has had dealings with the kidnappers or known intermediaries in the past.
But before all this started, just last month the International Maritime Organization sent a letter to all its members reiterating the "gravity of the issue of piracy and armed robbery against ships in the Gulf of Guinea," where the American ship was when it came under attack, "and the extreme violence exhibited" there. Statistics showed that pirate attacks, while down the world over, have sharply jumped in the Gulf of Guinea this year -- assaults allegedly perpetrated by criminal gangs who are looking for cargo ships with commodities or seeking hostages to ransom.
The letter discussed kidnappings along with brazen thefts of large ships' cargo, in which vessels are hijacked for several days to facilitate the laborious transfer of cargo onto the pirate's ship.
"That sort of criminal activity takes effective planning and coordination, logistical organization, technical knowhow and material support on a scale that strongly argues for something higher than random chance piracy being in play," said a maritime security source at sea near where the Americans were kidnapped.
The letter sent by the IMO also called attention to some "interim guidelines" urgently developed by organizations supported by NATO for mariners operating in the Gulf of Guinea, which includes an eerily specific warning about kidnapping, considering the C-Retriever's case:
"Kidnapping -- generally associated with the offshore oil industry and the political instability of the Niger Delta area. There are several instances of offshore supply vessels and occasionally other ship types being attacked."
The guidelines instructed ship owners in low-tech ways to defend against piracy, including everything from keeping radio communications to a minimum to physically blocking potential entry points. The guidelines also suggest turning of the ship's Automatic Identification System (AIS), which can be used by pirates to hone in on the ship's location, but the document emphasizes that the AIS be turned back on "immediately" if the ship is boarded, presumably to aid in a possible rescue.
At the time the guidelines were written at the beginning of 2013, they noted that the "pirate business model" in the Gulf of Guinea "does not primarily involve kidnap for ransom, therefore the crew of a ship does not in itself represent the 'value.'"
But the guidelines said that pirates in the Gulf of Guinea were more violent than the Somalia-based pirates on the other side of the African continent -- a much more publicized hotbed of piracy -- and instructed crewmembers "not to engage in a fight with the pirates, because this will entail great risk of the crew getting hurt or killed."
"Great care needs to be taken if your ship is boarded, as life is little valued by robbers," the guidelines say. "Compliance/submission to attackers is essential once a vessel has been taken."
Jack Cloonan, a former senior FBI agent now with Clayton Consultants, which specializes in international piracy, kidnapping and extortion, told ABC News Thursday the fact that the attackers reportedly singled out the Americans showed that the kidnappers do attach some value, at least monetary, to those lives.
"If you take the Americans, you get a good price, but at the same time you bring a lot of heat on you too," Cloonan said . "The initial demands will probably be ridiculously high and you can infer from that who you are dealing with. Are these people skilled? Do they have professional negotiators?... Do we know who this group is and is their end game actually money? Because if it is, I'm happy. I'm pleased and now I know it can be a negotiable end."
Neither the victims nor the attackers have been publicly identified. The company that owns the targeted ship, Edison Chouest Offshore, did not respond to comment Thursday. Representatives for both the White House and the State Department said Thursday their respective departments were "closely monitoring" the situation.