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LAGOS, May 20 (Reuters) - Nigeria's Dangote Flour Mills's half-year loss before tax widened by more than 10 percent to 4.74 billion naira ($29.1 mln), pressured by competition and security problems in northern Nigeria which hurt volumes.
The loss in the same period last year was 4.28 billion naira, the flour and pasta company said on Tuesday.
"Competition arising from the over-capacity in the flour milling sector remains a challenge. Volumes were also negatively impacted by the security challenges in northern Nigeria," Dangote Flour Mills, the Nigerian unit of South Africa's Tiger Brands, said in a statement.
Boko Haram, a militant group which wants Islamic sharia law more widely applied across Africa's most populous nation, has been waging a low level insurgency in northern Nigeria since 2009.
The Islamists grabbed world headlines with the abduction of more than 200 school girls a month ago from a remote village in the northeast and have claimed responsibility for series of car bombs and gun attacks, which has killed hundreds of people.
Dangote Flour Mills said turnover fell 2.8 percent to 18.58 billion naira during the six months period, and that trading conditions continued to be challenging with price discounting in the market putting pressure on margins.
Its shares rose by 0.13 percent to 7.70 naira on Tuesday, having fallen 22 percent this year.
"The outlook for the remaining period remains challenging but the business performance is expected to continue on an improvement trajectory," the company said.
Tiger Brands, Africa's second-biggest consumer foods maker, paid $188 million two years ago for a 63 percent stake in the company.
The South African company said last Thursday it took a $82 million writedown on the loss-making Nigerian business.
$1 = 163.10 naira Reporting by Chijioke Ohuocha; editing by Jane Baird and Susan Thomas