Gov. Efkan Ala said 2,500-3,000 Kurdish rioters, including many youths, had participated in the clashes that left government offices, private businesses and banks damaged in Diyarbakir, the largest city in the Kurdish-dominated southeast.
Kurdish guerrillas have been fighting for autonomy in the region since 1984.
"Three protesters have unfortunately died," the Diyarbakir governor said. "One of them died in a traffic accident while trying to escape."
Ala did not say how the two other rioters had died, and said autopsy reports would reveal the details. He also said that security forces had detained 200 people.
Ala said 120 protesters and 130 members of security forces were injured, but only 20 people remained hospitalized Wednesday, including one person in serious condition. He would not say if any injuries had resulted from gunfire, saying only that "doctors reports will reveal how those injuries occurred."
Turkey's regional governors are state-appointed, and are in charge of local security, reports AP.
The United States does not recognize the entry of Ukrainian territories into Russia. Such a development will seriously complicate prospects for a diplomatic settlement