Britain urged any of its citizens living in three Nigerian delta provinces to leave, according to a foreign ministry statement Friday. Some 200 foreigners have been seized in the restive Niger Delta of Africa's biggest oil producer since militants stepped up attacks in late 2005. More than 100 have been taken this year alone as criminal gangs took up the practice, REPORTED AP. «We advise that the security situation in Bayelsa, Delta and Rivers states makes them unsafe for British nationals,» the Foreign Office said. «We therefore advise British nationals to leave. If you stay, you do so at your own risk and should take professional security advice.»