The U.S. and some of its allies are considering plans to increase anti-piracy operations along Africa's west coast, spurred on by concerns that money from the attacks is funding a Nigerian-based insurgent group that is linked to one of al-Qaida's most dangerous affiliates.
Piracy in the Gulf of Guinea has escalated over the past year, and senior U.S. defense and counter-piracy officials say allied leaders are weighing whether beefed up enforcement efforts that worked against pirates off the Somalia coast might also be needed in the waters off Nigeria.
There has been growing coordination between Nigeria-based Boko Haram and al-Qaida in the Islamic Maghreb (AQIM), which was linked to the attack on the U.S. diplomatic mission in Benghazi, Libya, last September that killed four Americans, including the ambassador. Military leaders say AQIM has become the wealthiest al-Qaida offshoot and an increasing terrorist threat to the region.
It has long been difficult to track whether there are terrorist ties to piracy in the waters off Africa. But officials are worried that even if Boko Haram insurgents aren't directly involved in the attacks off Nigeria and Cameroon, they may be reaping some of the profits and using the money for ongoing terrorist training or weapons.
No final decisions have been made on how counter-piracy operations could be increased in that region, and budget restrictions could hamper that effort, said the officials, who spoke on condition of anonymity because they were not authorized to talk about emerging discussions between senior U.S. military commanders and other international leaders.
But officials say the solution could include continued work and counter-piracy training with African nations. The U.S. participated last month in a maritime exercise with European and African partners in the Gulf of Guinea.
"Maritime partnerships and maritime security and safety are increasingly important in the Gulf of Guinea region to combat a variety of challenges including maritime crime, illicit trafficking and piracy," said Gen. Carter Ham, head of U.S. Africa Command.
In recent weeks, Ham and other U.S. military commanders have bluntly warned Congress that the terrorist threat from northern Africa has become far more worrisome.
"If the threat that is present in Africa is left unaddressed, it will over time grow to an increasingly dangerous and imminent threat to U.S. interests, and certainly could develop into a threat that threatens us in other places," Ham told Congress earlier this month. "We've already seen from some places in Africa, individuals that -- from Nigeria, for example -- attempt to enter our country with explosives."
Piracy in the Gulf of Guinea has escalated from low-level armed robberies to hijackings and cargo thefts and kidnappings. Last year, London-based Lloyd's Market Association -- an umbrella group of insurers -- listed oil-rich Nigeria, neighboring Benin and nearby waters in the same risk category as Somalia.
Pirates have been more willing to use violence in their robberies, at times targeting the crew for ransom. And experts suggest that many of the pirates come from Nigeria, where corrupt law enforcement allows criminality to thrive and there's a bustling black market for stolen crude oil.
Typically, foreign companies operating in Nigeria's Niger Delta pay cash ransoms to free their employees after negotiating down kidnappers' demands. Foreign hostages can fetch hundreds of thousands of dollars apiece.
Lately, however, the attacks, which had traditionally focused on the Nigerian coast, have spread, hitting ships carrying fuel from an Ivory Coast port. In January pirates made off with about $5 million in cargo from a fuel-laden tanker near the port of Abidjan, and two weeks later a French-owned fuel tanker was hijacked in the same area.
Just days after that, three sailors were kidnapped off a U.K.-flagged ship off the coast of Nigeria, and late in February six foreigners were taken off an energy company vessel in that same region.
The International Maritime Bureau has raised alarms about the Ivory Coast attacks, calling the first January incident a "potential game changer" in piracy in the region because was the farthest ever from Nigeria in the Gulf of Guinea. And U.S. Navy Capt. Dave Rollo, who directed the recent naval exercise in the Gulf of Guinea that involved as many as 15 nations, said piracy in that area is not just a regional crime issue, it's "a global problem."
Meanwhile, over the past year, piracy off Somalia's coast has plummeted, as the U.S.-led enforcement effort beefed up patrols and encouraged increased security measures on ships transiting the region. After repeated urgings from military commanders and other officials, shipping companies increased the use of armed guards and took steps to better avoid and deter pirates.
According to data from the combined maritime
force, nearly 50 ships were taken by pirates in 2010 in the Gulf of Aden and Somali Basin and there were another close to 200 unsuccessful attempts. Last year, just seven ships were pirated there along with 36 failed attacks.
Even as defense officials warn about the growing threat, they acknowledge that increasing counter-piracy operations around the Gulf of Guinea presents a number of challenges.
In recent weeks, the U.S. Navy has had to postpone or cancel a number of ship deployments because of budget cuts, including a decision not to send the aircraft carrier USS Harry S Truman to the Persian Gulf. The U.S. has maintained two carrier groups in the Gulf for much of the past two years, as tensions with Iran have escalated.
U.S. Africa Command has no ships of its own, so any U.S. vessels needed for operations would have to come from other places, such as Europe or America.
And defense officials also note that it may be difficult to build as much international interest in the Gulf of Guinea attacks as those in the more heavily traveled shipping lanes on the northeastern side of the continent.