Spanish police say they have arrested the ringleaders of a human trafficking ring that allegedly brought Nigerian women to Spain and forced them into prostitution by threatening them with voodoo curses.Many of the 23 suspects arrested in nationwide raids were being charged on Saturday at a court in the southwestern city of Huelva.Police say the arrests were triggered by a woman who in February told police of the gang's intimidation tactics.The victims, aged 25 to 35, were forced to pay large sums of money to the gang members, who told the women...