Four 21-year-old soldiers have been arrested in Patra on suspicion of carrying out at least 10 armed robberies in the western port city.
The arrests were prompted by a robbery at a supermarket on Friday night, when a 57-year-old man was shot in the foot as he attempted to stop an armed assailant.
The robber grabbed 4,000 euros in cash but was arrested by police along with his getaway driver. Their arrest led authorities to two more men, who were also taken into custody. A fifth suspect is being sought.
Police said that the soldiers, who were not named, served at a local army camp and have allegedly been involved in at least 10 raids on stores in Patra.
The police force is due to hold a news conference on Monday, when more details will be made public.