The abductions reflected an increase in tensions in Turkey's mainly Kurdish south-eastern provinces after two protesters were killed on Friday in clashes with police in Yuksekova, a town near the Iraqi border.
The fatalities set off protests in other cities, raising fears an eight-month truce between the government and the outlawed PKK might be at risk.
The two officers and two sergeants were abducted on Sunday after 200 to 300 villagers blocked traffic on a road in the rural Lice area of Diyarbakir, some 310 miles from Yuksekova.
The group included PKK guerrillas who checked identity cards of people driving through before seizing the soldiers.
The military said it had deployed special forces to the area backed by manned surveillance flights, and the abductees were handed over to local police early yesterday after the intervention by Kurdish politicians.