LAGOS, Nigeria (AP) -- An alarming U.S. travel advisory warns Nigeria's Islamic uprising could expand out of the north and counsels against travel to 16 of the West African nation's 36 states, saying Americans have suffered violent crimes from kidnappings and rape to home invasions.
The advisory says nine foreign nationals including Americans died last year in kidnappings in southwest Nigeria, three of them killed by their captors during military-led rescue raids.
The advisory posted at the U.S. State Department website and dated Jan. 8 tells citizens to expect little help from law enforcers known for harassing and shaking down foreigners and Nigerians at checkpoints.
It says U.S. missionaries in northern Nigeria have received "night letters" -- covertly distributed specific written threats to their safety.
Pointing to possible targets of extremists, it says U.S. citizens should be particularly vigilant around government security facilities; churches, mosques, and other places of worship; locations where large crowds gather such as hotels, clubs, beer parlors, restaurants, markets and shopping malls; and all other areas frequented by expatriates and foreign travelers.
Thousands of people have been killed in a 4-year-old uprising by the Boko Haram terrorist network based in northeast Nigeria, many more Muslims than Christians, which continues despite an 8-month-long state of emergency that deployed thousands of troops to three states covering one-sixth of the country.
"Late 2013 saw an increase in Boko Haram attacks and clashes with Nigerian government security forces in northern Nigeria," the travel advisory says. "Boko Haram is known to descend on whole towns, robbing banks and businesses, attacking police and military installations, and setting fire to private homes."
It warns "U.S. citizens should be aware that extremists could expand their operations beyond northern Nigeria to other areas of the country." Boko Haram already operates in neighboring Chad, from which it kidnapped a French priest who was released earlier this month, and militants from Chad, Niger and Cameroon have been reported fighting alongside Boko Haram in Nigeria, raising fears the rebellion could also spread beyond Nigeria's borders.
The United States advises against all but essential travel to all 13 northern and central-northern Nigerian states as well as central Plateau state, for years the site of deadly ethnic-religious clashes, and the oil-rich southwestern states of Delta and Bayelsa, on the Gulf of Guinea where piracy is on the rise and militancy by activists demanding a bigger share of oil riches from a government embroiled in numerous corruption scandals.
Kidnappings of foreigners and attacks against Nigerian police forces in the Niger Delta region and in Lagos State, home to the commercial capital Lagos city, continue to be a danger, it says. "Criminals or militants have abducted foreign nationals, including U.S. citizens, from offshore and land-based oil facilities, residential compounds, and public roadways."
It adds that international companies and local authorities assert that the number of kidnapping incidents throughout Nigeria is underreported.
And home invasions "remain a serious threat," with armed robbers getting into even heavily guarded compounds.
"Violent crimes occur throughout the country," the advisory says. "U.S. citizen visitors and residents have experienced armed muggings, assaults, burglaries, armed robberies, carjackings, rapes, kidnappings, and extortion."
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