Pakistan's army ordered an inquiry on Monday into a former spy chief for co-writing a book with the ex-chief of an intelligence agency from arch-rival India that has stirred controversy on a range of issues.

The U.S. raid that killed Osama bin Laden is the most thorny issue in "Spy Chronicles," written by former chief of Pakistan's Inter Services Intelligence (ISI) Asad Durrani and A.S. Dulat, an ex-chief of Indian intelligence Research and Analysis Wing (RAW).

"A formal Court of Inquiry headed by a serving Lt. Gen. has been ordered to probe the matter in detail," the army said in a statement.