Gunmen holed up in a residential building in Tbilisi on Wednesday killed a soldier during a counter-terrorist operation that rocked the Black Sea nation's capital, doctors said.
The special task force soldier, whose gunshot "wounds were fatal, died," Tbilisi's Ingorokva hospital said in a statement.
Rustavi-2 television station reported that two more troops were hospitalised with gunshot wounds.
Explosions and gunfire were heard earlier Wednesday in Tbilisi's suburban Isani district as armed counter-terrorist units raided an apartment block, an AFP reporter witnessed.
Several suspected members of a terrorist group "refused to surrender and opened fire from automatic rifles and threw hand grenades at counter-terrorist units," Nino Giorgobiani, spokeswoman for Georgia's security service, said in a statement.
She added that one suspect had been detained and efforts were underway to detain several others.
Citing preliminary information, she said the assailants were not Georgian nationals but "members of a terrorist group."
"Investigation is under way both in Georgia and abroad to establish the suspects' criminal links," she added.
An AFP reporter on the scene heard multiple explosions and heavy gunfire in an area cordoned off by police on the outskirts of the city.
Rustavi-2 aired footage of a burning apartment in a multi-storey residential building, with dozens of camouflaged soldiers and an armoured vehicle deployed at the site.
Georgia has no recent history of major terror attacks.
Some 50 Georgians are believed to be fighting alongside Islamic State extremists in Syria and Iraq, Georgian officials have said.
They are mostly ethnic Chechen Muslim minority residents of a valley in the country's northeast, which has developed a reputation as a jihadist hotbed.
Ahead of and immediately after the 2008 Russia-Georgia war, Tbilisi accused Russian security services of staging terror attacks against civilians and police including planting an explosive device outside the US embassy in the capital.