Two Albanian soldiers were injured while trying to stop two Russians and a Ukrainian from entering a military plant, the Balkan country's defense minister said on Sunday.
One of the suspects jumped the fence of the Gramsh factory in central Albania, which is used for dismantling derelict weapons, and attacked the guards who confronted him, Niko Peleshi said.
"The Russian national reacted physically and he also used a spray which injured the two soldiers, who managed to warn the police," Peleshi said after visiting the soldiers in the hospital.
The 24-year-old man, identified by the initials MZ, was caught taking photographs of the facility.
A Russian identified as ST and aged 33 and a Ukrainian identified as FA and aged 25 were also arrested in a car near the factory.
The Albanian soldiers sustained eye injuries but are due to be released from hospital, the defense minister said.
Albanian Prime Minister Edi Rama said the three were "suspected of espionage."
"This is an incident that needs to be treated in a broader regional and political context," Peleshi added.
"It cannot be dismissed as an ordinary incident but we should not rush to conclusions either."
Albania, a member of Nato since 2009, has joined the United States and other western countries to condemn Russia's invasion of Ukraine and has introduced sanctions against Moscow.