ISTANBUL (AP) — Experts have started analyzing the black boxes recovered from a jet crash in Turkey that killed eight people, including western Libya’s military chief, the Turkish defense ministry said Thursday. The probe was being done in coordination with Libyan officials.

The private jet with Gen. Muhammad Ali Ahmad al-Haddad, four other military officers and three crew members crashed on Tuesday after taking off from Ankara, Turkey’s capital, killing everyone on board. Libyan officials said the cause of the crash was a technical malfunction on the plane.

Al-Hadad was the top military commander in western Libya and played a crucial role in the ongoing, U.N.-brokered efforts to unify Libya’s military, which has split, much like Libya’s institutions.

The high-level Libyan delegation was on its way back to Tripoli, Libya’s capital, after holding defense talks in Ankara aimed at boosting military cooperation between the two countries.

The wreckage was scattered across an area covering 3 square kilometers (more than a square mile), complicating recovery efforts, according to the Turkish Interior Minister Ali Yerlikaya.

A 22-person delegation, including five family members of those killed on board, arrived from Libya early on Wednesday to assist in the investigation.

Libya plunged into chaos after the country’s 2011 uprising toppled and killed longtime dictator Moammar Gadhafi. The country split, with rival administrations in the east and west, backed by an array of rogue militias and different foreign governments.

Turkey has been the main backer of Libya’s government in the west, but has recently taken steps to improve ties with the eastern-based government as well.