Nigerian oil officials said unchecked theft from pipelines may crimp the African nation’s ability to meet its target of adding 30 percent to crude output by the end of the decade. Stealing and sabotage cost the country 300,000 barrels of oil a day last year, Andrew Yakubu, group managing director of state-owned Nigerian National Petroleum Corp., said today at a conference in Abuja, the capital. Nigeria must do more to maintain its position as Africa ’s biggest producer, he said, adding that the country has a target to raise production to 3 million barrels a day by 2020, from about 2.3 million now. The nation’s oil output fluctuated by as much as 420,000 barrels a day between 2011 and 2013 amid pipeline attacks that halted flows from some fields. Nigeria has responded to theft by starting air surveillance of pipelines and allocating 15 billion naira ($91 million) for security […]