LAGOS (AFP) -- Nigeria may not be able to achieve a target of 10 percent economic growth this year because of the unrest in the oil-rich but restive Niger Delta, the governor of Central Bank of Nigeria (CBN) has said.

"The growth is not likely, at least from all indications, ostensibly because of the developments in the oil sector," Charles Soludo told reporters late Wednesday.

"Already we have lost quite a significant chunk in terms of output loss in the oil industry," he said.

Nigeria paid back the remaining 12.4 billion dollars, including arrears and interests, with part of its surging oil revenues.

Nigeria is Africa's biggest oil producer, accounting for a daily output of 2.6 million barrels, but 25 percent of that figure has been lost to unrest in the Niger Delta since January.

Separatist militants seeking local control of Nigeria's oil wealth have unleashed a wave of violence on oil firms and personnel in the Niger Delta.

Over 35 expatriate oil workers have been kidnapped in the past seven months but were released after spending days or sometimes weeks in captivity.

In the past two days alone, six foreign workers have been seized.