Nigeria's north has been under attack by the radical Islamic sect known as Boko Haram in the last 18 months and foreigners have become increasingly targeted as the violence has grown.
- In May, gunmen in northern state Kaduna killed a Lebanese and Nigerian construction workers while kidnapping another Lebanese employee.
- Later that month, kidnappers shot a German hostage during a rescue operation.
- Authorities said gunmen linked to Boko Haram kidnapped an Italian and British man last year who were later killed during a rescue operation by Nigerian soldiers.
- Chinese construction workers have also been killed by gunmen around Maiduguri, a north-eastern city in Nigeria.
The sect has been blamed for killing at least 729 people in 2012, according to an Associated Press count.
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