Former Turkish army colonel Cetin Oguz, 67, and his wife Asuman Oguz, 66, have survived an assassination attempt in Istanbul’s Besiktas district.
Two gunmen on a motorcycle attacked the pair as they were leaving a military base on Sunday.
Former colonel Oguz was wounded in the stomach, hospital sources said, adding that his condition remains stable. The sources did not reveal his wife's condition.
Turkish police have been searching for the attackers but have only found a motorcycle used in the shooting abandoned in a park near the military base.
A Turkish newspaper claimed on Sunday that Oguz was behind operations against militants from the far-left Revolutionary People's Liberation Party, or DHKP-C, during the 1970s, 80s and 90s.
Founded in 1978, the armed leftist group has revived its attacks in recent months.
Members of the group were also behind the killing of a senior prosecutor in Istanbul in March.
The group also claimed responsibility for an attempted grenade attack in January on police guarding Istanbul's Dolmabahce Palace.
The DHKP-C is considered a terrorist group by Turkey, the EU and the US.