A senior al-Qaeda militant arrested last month in Lebanon died Saturday while in military custody, the army said.
Majed al-Majed, a Saudi national who heads the Abdullah Azzam Brigades in the Levant, had been transferred to a military hospital in Beirut before his death, dpa reported.
He was wanted by Saudi Arabia and the United States on terrorism charges.
The official National News Agency said al-Majed died "after his health conditions deteriorated."
State Commissioner to the Military Court Judge Saqr Saqr told Lebanon's New television that al-Majed was in a coma before his death, adding that he had asked a forensic pathologist to examine his corpse.
About a month ago, al-Majed was reportedly in Syria where he pledged allegiance to the al-Qaeda-linked al-Nusra Front group chief Abu Mohammed al-Joulani.
The Abdullah Azzam Brigades claimed responsibility for an attack November 19 on the Iranian embassy in Beirut's southern suburbs, saying it was intended to put pressure on the Iran-backed Hezbollah movement to withdraw its fighters from Syria.
The Shiite Hezbollah has been fighting alongside the forces of Syrian President Bashar al-Assad against largely Sunni rebels.