KABUL, Afghanistan (AP) _ The Taliban's former defense minister died in a Pakistani jail in 2010, a spokesman for the insurgent group said Monday.

Little had been heard of Obaidullah Akhund since he was arrested by Pakistani authorities in 2007.

Taliban spokesman Zabiullah Mujahid said Monday that relatives have just recently been informed that Obaidullah died of heart disease in a Karachi prison on March 5, 2010.

Obaidullah was one of the top deputies of Taliban leader Mullah Mohammad Omar when the Islamist regime ruled Afghanistan in the 1990s. He was arrested in early 2007 in the southwestern Pakistani city of Quetta. At the time, he was the highest-ranking Taliban figure to be captured since the fall of the hardline regime in 2001.

The Taliban said they want Pakistani officials to provide details about his arrest, incarceration and death.

Obaidullah's name was among those floated earlier this year as possible representatives for potential peace talks with the insurgent group.

The Taliban are setting up an office in Qatar in the first step toward formal talks. The Obama administration is now considering the release of five top Taliban leaders from the U.S. detention center in Guantanamo as a starting point for negotiations. Republicans in Congress oppose the release of the prisoners.

Fighting has continued amid talk of negotiations with the Taliban. In southern Afghanistan on Monday a NATO service member died in an insurgent attack, the international military coalition said in a statement. Further details were not provided.

The death brought to at least 36 the number of international service members who have died since the beginning of the year.

Last year was the deadliest on record for civilians since the beginning of the Afghan war, with more than 3,000 killed primarily in insurgent attacks and bombings, according to a U.N. report released earlier in February. Civilians have also died in NATO operations, though in lower numbers.

Also Monday, Afghan investigators said they have confirmed that 15 civilians died in two NATO operations in Kunar and Kapisa provinces earlier this year. A NATO spokesman said the coalition regrets any civilian lives lost from the operations but that the international troops followed appropriate protocol in both instances.

In the more recent incident in Kapisa, German Brig. Gen. Carsten Jacobson, the spokesman, said it was not clear if all the deaths were caused by the NATO operation.