Despite international naval efforts to counter acts of piracy in the waters off Somalia, pirates in this region continue to increase not only the sophistication and geographic range of their attacks, but also the level of violence against hostages. Hostages are also being detained longer, as pirates hold out for ransom payments that now reportedly average over $5 million per ship. Heightened military presence in an internationally recommended transit corridor in the Gulf of Aden has reduced attacks in that area, but pirates have adopted tactics that now allow them to attack more than 1,000 nautical miles off the Somali coast. Pirate attacks in the Gulf of Aden, the Red Sea, and the waters far off Somalia's eastern coast, including the Arabian Sea, have been attributed to Somali pirates. The number of attacks in this area, which had roughly doubled annually from 2007 to 2009, rising from 51 reported attacks to 217, appeared to level off in 2010, when 219 attacks were reported. Attacks in the Gulf of Aden declined by more than half in 2010, attributed in large part to international naval patrols. Attacks east and south of Somalia, however, increased substantially, up from 19 reported attacks in 2008 and 80 in 2009 to over 140 in 2010. As of March 2011, Somali pirates had been sighted as far east as off the coast of India, and as far south as the Mozambique Channel. The two monsoon seasons in the Indian Ocean appear to dampen pirate activity in these waters, but, with the end of the winter monsoons, the spring months of 2011 have corresponded to a spike in attacks. The International Maritime Bureau (IMB) reports that, in 2010, over 1,016 crew members on dozens of hijacked vessels were taken hostage by Somali pirates. Most were released following ransom negotiations, but at least 13 were injured and 8 killed. In the first three months of 2011, IMB data indicate that almost 100 vessels in the region reported being attacked, with 15 successful hijackings involving approximately 300 hostages. These attacks represent a substantial increase from the same period last year, when 35 vessels were attacked in the waters off Somalia. At least seven hostages have been killed to date in 2011, including four Americans. As of April 2011, Somali pirates were holding over 26 ships and 530 crew hostage while seeking ransoms. U.S. ships represent a small but high-profile percentage of those attacked by Somali pirates. In March 2011, the Maersk Alabama , which had been the target of a widely reported attack in 2009 and an unsuccessful attempt in 2010, was approached by suspected pirates for a third time. The Alabama , which now has armed security guards onboard, deterred the pirates with defensive manoeuvres. Two U.S. warships were attacked by Somali pirates in 2010. The deaths of four Americans on February 22, 2011, onboard the sailboat Quest mark the first known American casualties during a Somali pirate attack. The Quest had been hijacked less than 200 nautical miles off the coast of Oman four days prior, and the pirates were reportedly in the process of taking it back to an anchorage off the Somali coast when they were intercepted by four U.S. Navy vessels, including an aircraft carrier, a guided missile cruiser, and two destroyers. Details surrounding the incident remain under investigation, but, according to U.S. Navy reports, pirates onboard the Quest fired a rocked-propelled grenade (RPG) at one of the destroyers, the USS Sterrett , after negotiations broke down with two pirates who had boarded the Sterrett for talks with a Federal Bureau of Investigation (FBI) hostage negotiator. A Navy SEAL team subsequently boarded the Quest and found that the American hostages had been shot and fatally wounded. Some Somali accounts differ with the Navy account, claiming that the hostages were caught in crossfire during a rescue attempt by the SEALs. Two pirates were found dead onboard, and two others were killed during the raid. The remainder, 13 Somalis and 1 Yemeni, were captured and brought to Norfolk, VA, where they have been indicted by a grand jury. An additional indictment was issued in March for Mohammad Saaili Shibin, who is accused of serving in a leadership role as the pirate gang's hostage negotiator. Shibin, who reportedly earned $30,000 for his negotiating role in the 2010 hijacking of a chemical tanker, was apprehended in Somalia in a joint operation by Somali security forces and the FBI in April. He is the first piracy suspect captured onshore in Somalia to be tried in the United States. Another suspected pirate negotiator, Ali Mohamed Ali, was arrested at Dulles International Airport on April 21, 2011, in relation to the 2008 hijacking of a Danish vessel carrying American cargo (see below). To date, U.S. courts have tried Somali pirates from three other incidents. In November 2010, five Somalis involved in the April 2010 attack on the U.S. Naval frigate USS Nicholas were the first to be convicted of piracy by a U.S. jury since 1820. They were given life sentences plus 80 years for related firearms charges by a civilian court in Norfolk, VA, in March 2011. A Somali involved in the 2009 hijacking of the Maersk Alabama , Abduwali Abdiqadir Muse, was sentenced by a New York court in February 2011 to almost 34 years in prison on charges of hijacking, kidnapping, and hostage taking. Muse was not convicted of piracy. A federal judge dismissed piracy charges against six Somalis implicated in the April 2010 attack against another warship, the USS Ashland , in August 2010. One of the defendants, Jama Idle Ibrahim, pled guilty to related charges and to conspiracy to commit piracy in a 2008 attack on a Danish ship carrying American cargo. Ibrahim, who reportedly received a $17,000 share of a $1.7 million ransom for the Danish vessel, is now serving a 30-year term for both crimes. The remaining five face seven other charges; prosecutors have appealed the decision to dismiss the piracy charge. The U.S. government and the international community have undertaken an array of efforts to prevent and deter pirate attacks. Various authorities have issued warnings to vessels in the waters off the Horn of Africa and continue to provide guidance on measures to maximize their safety while transiting the area. In addition to an existing advisory warning to U.S. vessels regarding the threat of piracy in the waters off the Horn issued by the U.S. Department of Transportation Maritime Administration (MARAD), the U.S. Coast Guard has, in the wake of the Quest attack, issued a warning strongly advising all U.S. registered yachts and sailing vessels against passage in the Gulf of Aden, Arabian Sea, Somali Basin, and western parts of the Indian Ocean. These vessels are particularly vulnerable to attack because of their low speed and low freeboard (the height of a ship's deck above the water level). The shipping industry, in coordination with the combined naval forces conducting counter-piracy operations, has produced guidance, known as Best Management Practices (BMPs), for mariners transiting these high-risk waters. The U.S. Navy continues to conduct counter-piracy operations in the region, primarily through the Combined Task Force 151 and NATO's Operation Ocean Shield. The European Union and NATO have extended the mandates for their counter-piracy missions through the end of 2012. China and Russia have assisted EU forces in escorting World Food Program relief shipments and China has shown willingness to improve its cooperation with the coalition task force providing security escorts in the Maritime Security Patrol Area in the Gulf of Aden. International coordination of anti-piracy efforts has improved over the past two years, both at sea and in the region, but U.S. civilian and military officials continue to stress the importance and difficulty of finding solutions to the problem of instability ashore in Somalia. To that end, the African Union (AU) has extended the mandate of their peacekeeping force in the country, the African Union Mission to Somalia (AMISOM). In December 2010, the U.N. Security Council passed Resolution 1964, extending its approval of AMISOM's mandate through September 2011 and raising the troop level to 12,000. The United States had provided training, logistics support, and assistance worth over $365 million to AMISOM. The United States has also provided over $85 million in assistance to the Somali Transitional Federal Government (TFG) security forces. AMISOM and TFG forces continue to face attacks from Al Shabaab, an Islamist insurgent group with ties to Al Qaeda. Capacity building efforts for these forces have focused on stabilizing Mogadishu before extending beyond the capital, and the TFG has yet to demonstrate the ability to expand its authority along the coast. Further complicating the security situation is a growing debate about the TFG's legitimacy as its mandate approaches expiration in August 2011. U.N. Secretary-General Ban Ki-moon released his latest report on piracy off Somalia to the Security Council in October 2010. He reported that ships following "best practices" developed by the maritime industry had a significantly lower risk of being hijacked. The Secretary-General also reported on the situation in Somalia in December 2010 and gave an update on international anti-piracy efforts. He has noted a request from the TFG president for support to develop Somalia's security forces and train its coast guards as part of international efforts to address piracy. The African Union has called on the Security Council to approach the Somali piracy issue "in a holistic manner, with the view to effectively addressing its underlying causes and other equally serious threats which affect the livelihood and well-being of the Somali people."